GOST R ISO 16962-2012
GOST R ISO 16962−2012 Coating based on zinc and/or aluminum on steel. The determination of the thickness, chemical composition and coating mass per unit area of surface by atomic emission spectrometry with glow discharge
GOST R ISO 16962−2012
Group B39
NATIONAL STANDARD OF THE RUSSIAN FEDERATION
COATINGS BASED ON ZINC AND/OR ALUMINUM ON STEEL
The determination of the thickness, chemical composition and coating mass per unit area of surface by atomic emission spectrometry with glow discharge
Zinc and/or aluminium based coatings on steel. Determination of coating thickness, chemical composition and mass per unit area by glow-discharge atomic-emission spectrometry method
OKS 71.040.40
AXTU 0709
Date of introduction 2013−09−01
Preface
1 PREPARED AND SUBMITTED by the Technical Committee for standardization TC 145 «monitoring Methods of steel products» on the basis of authentic translation into the Russian language of the standard, referred to in paragraph 3
2 APPROVED AND put INTO EFFECT by the Federal Agency for technical regulation and Metrology of June 27, 2012 N 121-St
3 this standard is identical with ISO 16962:2005* «Chemical analysis of surfaces. Analysis of metal coatings based on zinc and/or aluminum by the method of optical emission spectrometry with glow discharge» (ISO 16962:2005 «Surface chemical analysis — Analysis of zinc-and/or aluminium-based metallic coatings by glow-discharge optical-emission spectrometry»).
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* Access to international and foreign documents referred to here and hereinafter, can be obtained by clicking on the link to the site shop.cntd.ru. — Note the manufacturer’s database.
The name of this standard changed with respect to names specified international standard for compliance with GOST R 1.5−2012 (subsection 3.5).
In applying this standard it is recommended to use instead of the referenced international standards corresponding national standards of the Russian Federation and interstate standards, details of which are given in Appendix YES
4 INTRODUCED FOR THE FIRST TIME
Application rules of this standard are established in GOST R 1.0−2012 (section 8). Information about the changes to this standard is published in the annual (as of January 1 of the current year) reference index «National standards» and the official text changes and amendments — in monthly information index «National standards». In case of revision (replacement) or cancellation of this standard a notification will be published in the upcoming issue of the monthly information index «National standards». Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet (gost.ru)
1 Scope
This standard specifies atomic emission spectrometer with glow discharge method of determination of thickness, chemical composition, mass per unit surface area of metallic coatings consisting of materials based on zinc and/or aluminium, steel. Of the alloying elements determine the Nickel, iron, silicon, lead and antimony.
The method is applicable for determining a mass fraction of elements in the following ranges: zinc, from 0.01% to 100%; aluminum from 0.01% to 100%; Nickel, from 0.01% to 20%; iron from 0.01% to 20%; silicon, from 0.01% to 10%; lead — from 0.005% to 2%; antimony from 0.005% to 2%.
2 Normative references
This standard uses the regulatory references to the following international standards*:
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* The table of conformity of national standards international see the link. — Note the manufacturer’s database.
ISO 14707:2000 Surface chemical analysis. Optical emission spectrometry glow discharge (GD-OES). Introduction for use (ISO 14707:2000 Surface chemical analysis — Glow discharge optical emission spectrometry (GD-OES) — Introduction to use)
ISO 14284:1996 Steel and iron. Selection and preparation of samples for the determination of chemical composition (ISO 14284:1996, Steel and iron — Sampling and preparation of samples for the determination of chemical composition)
ISO 17925:2004 Coating based on zinc and/or aluminum on steel. Determination of coating mass per unit surface area and chemical composition. Gravimetry, atomic emission spectrometry with inductively coupled plasma and flame atomic absorption spectrometry (ISO 17925:2004 Zinc and/or aluminium based coatings on steel — Determination of coating mass per unit area and chemical composition — Gravimetric, inductively coupled plasma atomic emission spectrometry and flame atomic absorption spectrometry)
3 the essence of the method
This method is based on:
a) cathodic sputtering of the coating material into the glow discharge device with constant current or radio frequency;
b) the excitation of analyte atoms in the plasma discharge generated in the glow discharge device;
c) spectrometric measuring the intensity of characteristic radiation spectral lines of the analyte atoms depending on the sputtering time (depth profile);
d) converting the profile depth in units of intensity relative to time to retrieve the value of the mass fraction using the calibration functions (quantitative). The dependence of the calibration set, measuring calibration samples of known chemical composition and spraying speed.
4 Equipment
4.1 Optical emission spectrometer with glow discharge
The necessary equipment includes optical emission spectrometer, consisting of a source of a glow discharge type lamp of the Grimm [1] or a similar source, glow discharge (DC or RF source) and a spectrometer system for simultaneous steps in ISO 14707 having suitable spectral lines for the identified elements (Annex b for the proposed lines).
The inner diameter of the hollow anode in the glow discharge source should be from 2 to 8 mm. Can be recommended cooling device for thin samples, which is a metal block with a circulating cooling liquid, however, its use is not strictly required when using this method.
Because the definition is based on the continuous spraying of the surface coating, the spectrometer must be equipped with a digital reference system for simultaneous measurement of time and intensity of radiation. Can be recommended system that can set the speed of data registration in the spectral channel not less than 500 measurements per second for use in this standard is the acceptable rate of 2 measurements per second.
4.2 Required performance characteristics
4.2.1 General requirements
In 4.2.2 and 4.2.3 are recommended instrumental performance, evaluated according
Note — set up spectrometer for analysis generally requires readily available to repeat the possibility of adjusting various experimental parameters.
4.2.2 Requirements for repeatability
The real test carried out to confirm the ability of the device to provide the requirements for repeatability.
Perform 10 measurements of radiation intensity in a homogeneous sample with a mass fraction of analyte in more than 1%. The settings of the glow discharge should be the same as in the actual analysis of surfaces. Measurements are performed using a stabilization time of discharge not less than 60 seconds and integration time of the radiation in the range from 5 to 20 C. Each measurement is performed on the newly prepared surface of the sample. Calculated relative standard deviation of the results of 10 measurements. The relative standard deviation must comply with any requirements and/or characteristics relevant to intended use.
Note — a Typical relative standard deviation defined in this way, 2% or less.
4.2.3 detection Limit
4.2.3.1 General requirements
The limits of detection depend on the instrument and sample matrix. Consequently, the detection limit for a particular analyte cannot be uniquely defined for all the employed equipment or of the totality of alloys based on Zn/AI, which are addressed in this standard.
The detection limit for each analyte is acceptable if it is equal to or less than one fifth of smallest mass fraction of analyte expected in the coating, or equal to one-fifth the mass fraction of analyte in the lower end of the range specified in section 1 of this standard.
4.2.3.2 SNR method
In this method, estimates of detection limit considering the ratio signal/noise, and this method is usually called SNR method.
To determine the detection limit of the specific analyte should:
1) choose a solid sample for use as a blank sample (blank). The chemical composition of this sample should be similar to the analyzed composition of the coating and is expressed in the same units. The content of the analyte in the sample should be less than 0.1 µg/g of substance;
2) to perform ten repeated measurements on a single sample. For each measurement set the integration time of radiation intensity at the analytical wavelength of 10 s. It is a measurement of the background radiation intensity. The conditions used for the excitation of the glow discharge should be the same as in the analysis of samples of coatings. The stabilization time of the glow discharge must be sufficient to provide stable signals for each measurement sample in the idle experience, and to perform quantitative measurements. Each measurement is performed on the newly prepared surface of the sample for the blank experience;
3) calculate the detection limit expressed in mass fraction of the analyte using the following equation
where is the detection limit;
— the standard deviation of 10 measurements of radiation intensity of background, as specified in the procedure in listing 2);
analytical sensitivity obtained from the calibration of the instrument, expressed as the intensity ratio to the mass fraction.
If the value of the calculated detection limit is unacceptable, the test is repeated. If the re value is also unacceptable to the analysis the samples must be identified and corrected causes of the discrepancy.
4.2.3.3 Method SBR-RSDB
This method requires the use of a blank sample, it is commonly called SBR-RSDB method (the ratio of signal-to-background relative standard deviation of the background). Operations are performed in the following way:
1) choose solid sample with chemical composition similar to the analyzed coatings, in which the mass fraction of analyte is known or more than 0.1%. Using the analytical line, prone to self-absorption (6.1), the mass fraction of the analyte should not exceed 1%;
2) on this sample have three identical dimensions. For each measurement integrates the radiation intensity of the analytical line for 10 s. the Conditions for excitation of the glow discharge should be similar to those used in the analysis of the samples with coating. The measurements were carried out for a time sufficient to obtain stable signals for the quantitative evaluation of the radiation intensity. Each measurement is performed on the newly prepared surface of the sample. Average values of three measurements of radiation intensity;
3) At a distance of about 0.2 nm from the maximum of the analytical lines choose an area free from spectral lines, and perform ten measurements, integrating the intensity of each measurement for 10 s. make a measurement of the background intensity. Conditions of measurement must be the same as in the procedure in listing 2). For each consecutive individual measurements used newly prepared surface of the sample. Calculate the average value of the relative standard deviation of 10 consecutive measurements of the background intensity;
4) limit of detection calculated according to the following formula
where is the detection limit;
— mass fraction of analyte in the sample;
— the average radiation intensity in the maximum of [the procedure of listing 2)];
— the average intensity of the background [procedure on transfer 3)].
If the calculated detection limit does not meet the requirements, repeat the test. If the second value of the detection limit is acceptable, then find out why and resolve the discrepancy prior to sample analysis.
5 Sampling
Sampling is carried out according to ISO 14284 and/or other normative documents.
If such standards do not exist, you must comply with the manufacturer’s instructions of materials or other appropriate documentation. Avoid the edges of the strip. Sample size shall be suitable for the applied method of analysis. Usually fit round or rectangular samples of dimensions (diameter, width and/or length) of 20 to 100 mm.
The sample surface is washed with a suitable solvent (high-purity acetone or ethanol) to remove oils. Dry the surface in a stream of inert gas (argon or nitrogen) or clean, free from oil, compressed air, being careful not to touch the surface of a pipe of gas supply. To facilitate the removal of surface dirt, wipe gently with a damp, soft, lint-free cloth or paper. After cleaning, the surface is washed with solvent and dried as described above.
6 analysis
6.1 Selection of spectral lines
For each analyte choosing appropriate spectral lines, taking into consideration several factors:
— spectral range of the used spectrometer;
— the range of mass fraction determined by the analyte;
— sensitivity of the spectral lines and the spectral interference from other elements present in the samples.
As considered in this standard analyte, which are the main elements in the samples, special attention should be paid to the effect of self-absorption of some sensitive spectral lines (the so-called resonance lines). Self-absorption is the reason for the nonlinearity of the calibration dependencies at higher levels of the mass fraction of analyte, therefore, self-absorption must be avoided in determining the basic elements. The app provides guidelines concerning the appropriate spectral lines. You can use other spectral lines, in addition to these, if they have suitable characteristics.
6.2 optimization of the system configuration of the glow discharge spectrometer
6.2.1 General requirements
Preparing the spectrometer to the work carried out on the instructions of the appliance manufacturer or in other documented procedures.
Parameters device must be:
— optimal conditions for the atomization of the sample to reduce analysis time without overheating surfaces;
— optimal (correct) form of the crater for an accurate assessment of the thickness of the coating;
— constant conditions of excitation of the plasma glow discharge in the calibration and analysis for optimum accuracy.
When implementing the three above conditions are sometimes necessary to resort to compromises.
In addition, following the instructions provided by the manufacturer of the spectrometer, you must make sure that the entrance slit is properly adjusted. This ensures the measurement of the intensity at the maximum of the spectral lines with an optimal signal-to-background. For more information, see ISO 14707.
6.2.2 setting the discharge parameters of the DC power source
6.2.2.1 General requirements
Modern spectrometers glow discharge have the ability to control and measure electrical parameters (current, voltage and power), allowing to support any of these parameters constant while changing the pressure of the carrier gas. The spectrometers of the early generations is often missing is a system of automatic pressure regulation, but to get the same result, the pressure can be adjusted manually. You must perform one of the following procedures.
6.2.2.2 Mode of constant values of current and voltage
As the two control parameters of the applied current and voltage. For the source of the glow discharge set the power level to maintain a regime of constant values of current and voltage, in this case, set the values of current and voltage specified by the manufacturer. If no recommended values, set the voltage to 700 V and the current value: 5 to 10 mA for the anode with a size of 2 or 2.5 mm; from 15 to 30 mA for the anode with a size of 4 mm; from 40 to 100 mA for anode size 7 or 8 mm. When the unknown values of the optimal values of current, it is recommended to start with a value close to the middle of the recommended range.
Set the high voltage on the detectors, as indicated
Set up the parameters of the discharge in accordance with 6.2.5, adjusting the first current and optionally the voltage.
Carry out optimization of the shape of the crater in accordance with 6.2.6 by regulating the voltage. Selected conditions for the control parameters are then used as in the calibration and in the analysis.
6.2.2.3 Mode of constant values of current and pressure
As the two control parameters of the applied current and the pressure of the working gas in the lamp. Set the power level for the source of the glow discharge to maintain a constant current value, in this case, set the value of the current specified by the manufacturer. If the recommended values are not suitable, set the current value: 5 to 10 mA for the anode with a diameter of 2 or 2.5 mm; from 15 to 30 mA for the anode with a diameter of 4 mm or from 40 to 100 mA for anode with a diameter of 7 mm or 8 mm. When the unknown optimal value of the current, it is recommended to start with a value close to the middle of the recommended range. A typical spray coating on the test sample and adjust the pressure by changing the voltage, until they reach values of approximately 600 for this coverage.
Set the high voltage on the detectors, as described
Adjust the control parameters of the discharge in accordance with 6.2.5, first adjusting the current and, if necessary, pressure.
Carry out optimization of the shape of the crater, as described in 6.2.6, by regulating the pressure. Before spraying the coating on sample a new type of make a trial run in order to check that the voltage does not change by more than 5% compared to the previously selected value. If this happens, adjust the pressure to achieve the correct values. Selected conditions for the control parameters are then used as in the calibration and in the analysis.
The intensity of the radiation varies with the values of current, voltage and, possibly, pressure [4]. Therefore, it is very important that these parameters were maintained as closely as possible on the same level as during the analysis of samples with coating and in the calibration. As it is practically impossible to maintain all three parameters constant for all samples in the first place it is necessary to maintain constant values of current and voltage, leaving the pressure is a variable parameter. There is a method for correcting voltage and current, using variations using the empirical derivative of the function [4], this type of correction is often implemented in the software of the spectrometer based on the method of normalization of the intensity in accordance with equation (A. 2) Appendix A. However, such adjustments of the voltage and current are not included in this standard method. If the spectrometer software the user must ensure that the adjustment voltage to current is disabled to ensure a correct implementation of the method on this device.
6.2.3 setting the discharge parameters of an RF source
6.2.3.1 General requirements
Currently, most radio frequency (RF) sources, works with constant power input and constant pressure. Other modes also exist, for example constant stress and pressure and constant effective power and voltage. These modes are likely to become more common in the future. All RF modes of operation are permitted in this standard if they provide the conditions listed
6.2.3.2 Mode of constant values of power and pressure
As control parameters used by the power and pressure of the working gas in the lamp. Beginning with the establishment of the values of power and pressure suggested by the manufacturer. If the recommended values are not suitable, apply a set of values of power and pressure, close to the middle of the range commonly used for profiling the depth of the crater metal of the samples. Measure the speed of deepening (i.e., the depth value in a unit of time) on a sample of iron or steel. Adjust power by setting the speed of deepening (penetration) for approximately 2 to 3 µm/min.
Set the high voltage on the detectors, as indicated
Adjust the discharge parameters, as described in 6.2.5, adjusting the first power applied and, if necessary, pressure.
Optimize the shape of the crater, as described in 6.2.6, by regulating the pressure.
A second measurement of the speed of the inlet for the sample of cast iron or steel and adjust the power. If necessary, return the speed to values lying in the range of 2 to 3 µm/min Repeat cycles of power control and pressure until significant changes in the rate of deepening or shape of the crater. Pay attention to the values of installed capacity and pressure in those units in which calibrated the instrument. These conditions are then used in the calibration and analysis.
6.2.3.3 constant power value and the changing values of the DC voltage
As the two control parameters using the power and changing the DC voltage. First apply a series of power values and adjust the pressure of the working gas in the lamp to achieve a standard displacement as suggested by the manufacturer. If the recommended values are not suitable, then choose the value of the power and changing the DC voltage close to mid ranges, usually used to achieve the required depth profiling of metal samples. The devices are equipped with a pressure control, this can be achieved automatically. Measure the speed of deepening (i.e., depth values per unit of time) for samples of cast iron or steel. Power control allows you to change the speed of deepening approximately 2 to 3 µm/min.
Set the high voltage of the detectors, as mandated
Adjust the discharge parameters, as described in 6.2.5, adjusting the first power and, if necessary, the offset DC voltage.
Optimize the shape of the crater, as described in 6.2.6, by changing the bias voltage DC.
Re-measure the speed of deepening of the (penetration) for a sample of cast iron or steel. Set up apply power, if necessary, returning to the speed of 2 to 3 microns/min Repeat cycles of power regulation and bias voltage as long as there will be no significant changes in the rate of deepening or shape of the crater. If necessary, adjust the offset DC voltage to establish the correct values. Pay attention to unit power and shifted DC voltage, is used in the specific device. These conditions are then used in the calibration and analysis.
6.2.3.4 Mode of constant values of the effective power and radio frequency (RF) voltage
As the two control parameters are used, the effective power and the RF voltage. Constant, the effective power is defined in this standard as applied power minus (minus) of the reflected power and the «dark power», measured with a sample placed, but without the plasma (in the vacuum). The RF voltage is defined here as the RMS voltage, i.e. the RMS (effective) voltage across the electrodes.
The power source of glow discharge with a constant effective power and constant RF operating voltage, using a set of typical values recommended by the manufacturer. If you prefer other values of voltage can be, for example, to set the set values of the RF voltage up to 700 V, and the values of power range from 10 to 15 W for the anode with a size of 4 mm. If there is no prior knowledge about the values of optimal power, it is recommended to start with values that are approximately in the middle of the recommended range.
Set the high voltage detectors in accordance with
Adjust the discharge parameters, as described in 6.2.5, adjusting the first power and, if necessary, RF voltage.
Optimize the shape of the crater in accordance with 6.2.6 by changing the RF voltage.
Re-measure the speed of penetration of a sample of cast iron or steel and regulate the capacity, if necessary, returning to the values of 2 to 3 µm/min Repeat cycles of power control and offset DC voltage until then, is not observed significant changes of the rate of penetration or crater. If not, adjust the offset DC voltage to achieve the correct value. Pay attention to the fact that it uses an offset DC voltage in the units specified in the instrument. These conditions are then used in the calibration and analysis.
6.2.4 configuring the high voltage detectors
Choose samples with coatings of all types, which purport to analyze. Using these samples include the source and observe the output signals from the detectors for the analyte atoms. Regulate the high voltage of the detectors thus, to ensure sufficient sensitivity for the low mass fraction of analyte, but without saturation of the detector system with the highest mass fractions of analyte.
6.2.5 setting the parameters of discharge
For each type of analyzed samples perform a full measurement of depth of cover, spraying the material sample in a glow discharge for quite a long time to completely remove the coating to continue the process to the penetration into the base material. Watching the intensity of emission as a function of time of spraying (which is quantitatively consistent with the depth of coverage), confirm that the selected source configuration gives stable emission signal over the entire depth profile (cover) to the base. Unstable signal emission may indicate thermal instability of the surface of the sample; cooling the sample affects the process. If you do not find the conditions of stability of signals of emission, gradually reduces the value of one of the control parameters and test again. If the stability is still not satisfactory, gradually reduce the value of another control parameter and continue the measurement. The procedure is repeated until then, until we find the conditions for obtaining a stable signal emission.
6.2.6 optimization of the shape of the crater
Spray one of the samples of brass (6.3.2) or unknown sample with a typical coating based on zinc and/or aluminum to a depth of approximately 10 to 20 µm (when using the sample covering the crater depth should not go beyond the coating layer). Measured configuration of the shape of the crater with a profilometer. Repeat this procedure on the brass sample and the sample coated several times using slightly different values of control parameters. Choose the conditions under which get the best option of a crater with a flat bottom.
6.2.7 Preliminary validation of the operating parameters
You should ensure that the selected operating parameters adequately meet the requirements given in 4.2. If these requirements are not satisfactory, it’s necessary to tune performance parameters to the required level.
6.3 Calibration
6.3.1 General requirements
The calibration system is to determine for each analyte and analytical signal for the selected spectral lines of the calibration dependence, which is presented in A. 2 or A. 3 of Annex A. When performing the calibration it is necessary to know how the chemical composition and the sputtering rate (the rate of loss of mass) of the calibration samples.
6.3.2 Calibration samples
6.3.2.1 General requirements
Possible to apply spectral calibration samples made in the status of a certified standard sample of the composition. Samples for calibration should not be entirely similar to the coating materials according to the chemical composition, but it is necessary that the speed of spraying was reliably determined and are reproducible. It should be borne in mind that pure or nearly pure samples of zinc are not recommended because of difficulties in obtaining reproducible and stable results for the velocity dispersion of zinc. Moreover, high-purity metals are not needed for correct calibration in the field of high content of the analyte, but they are able to assess spectral background. When choosing calibration samples the most important are the following conditions:
a) must have not less than five calibration samples for each analyte in the range of values from zero to the highest mass fraction of analyte;
b) samples should be homogeneous.
Based on these General requirements, you can use the following the calibration samples not exclude the use of samples of alloys of other types, containing analyte.
6.3.2.2 Calibration samples made from brass
Choose at least two brass samples with a mass fraction of zinc from 25% to 50% aluminum, from 1% to 4%, and lead — from 1% to 4%.
6.3.2.3 Calibration samples of zinc-aluminum alloys
Choose at least two samples of zinc-aluminum alloy with a mass fraction of zinc from 40% to 90%.
6.3.2.4 Calibration samples of iron or low-alloy steel
Choose at least two samples of iron or low-alloy steel with a mass fraction of iron more than 98%. Mass fraction of iron can be determined by subtracting from 100% the sum of the mass fractions of all other known elements.
6.3.2.5 Calibration samples of high-alloy steel
Choose at least two samples of high-alloy steel with a mass fraction of Nickel from 10% to 40%.
6.3.2.6 Calibration samples of Nickel alloys
Choose at least one sample of the alloy based on Nickel with a mass fraction of Nickel is higher than 70% (if the mass fraction of Nickel above 20% (see section 1), require higher speed spraying of zinc-Nickel alloys, and points on the calibration curve are determined as the product of the velocity dispersion and the mass fraction).
6.3.2.7 Calibration samples of silicon-aluminum alloys
Choose a minimum of one sample from the silicon-aluminum alloy with a mass fraction of silicon from 5% to 10%.
6.3.2.8 Calibration sample of high-purity copper
Choose a sample of high purity copper with a mass fraction of analyte is less than 0.001%. This sample can be used as the zero point for all analytes, with the exception of copper.
6.3.3 Certified standard samples and reference materials (samples comparison) used for the calibration
6.3.3.1 General requirements
In the case of validation of the analytical results should be placed in the certified standard samples (6.4). As additional calibration samples can be used samples, although possibly the use of other types of samples.
6.3.3.2 comparison Samples of electrolytic zinc-Nickel coatings
Prepare samples comparison with electrolytic coating with a mass fraction of Nickel less than 20%. Determine the coating mass per unit area and chemical composition of the coatings of these samples certified standard methods such as ISO 17925.
6.3.3.3 Samples comparison with electrolytic zinc coating
Prepare samples comparison with electrolytic coating with a mass fraction of zinc more than 30% and a mass fraction of iron is above 5%. Determine the mass of coating per unit surface area and chemical composition of the coatings of these samples certified standard methods such as ISO 17925.
6.3.3.4 Samples comparison with zinc-aluminum coating
Prepare comparison samples coated with a mass fraction of zinc more than 10% and a mass fraction of aluminum, more than 5%. Determine the chemical composition of the coatings of these samples certified standard methods such as ISO 17925.
Notes
1 Reference materials (samples comparison) are materials or substances in which the value of one or more properties (characteristics) are fairly uniformly, consistently and correctly installed to use it as calibration for the calibration of instruments, to assess a measurement method or for analyte determination in materials.
2 State standard samples is a standard sample having certificates for one or more properties, certified according to the method, which is approved by their traceability (the unity of measurement), in clearly defined units in which the values of characteristics are expressed, are certified with the uncertainty of the adopted confidence level. Standard samples (SRM) correspond to the certified standard samples (CRM) issued by the National Institute of standards and technology, Gaithersburg, MD, USA.
6.3.4 determination of the sputtering rate calibration samples
The term «speed spraying» should be understood as equivalent to the rate of loss of mass during sputtering in the glow discharge plasma. The term «relative velocity spraying» should be understood as the dispersal rate of the sample divided by the dispersal rate of the reference sample, sputtered under the same conditions. If the areas which were diffused, for the analyzed sample and the comparison sample are the same, then the relative dispersal rate equivalent to the relative evaporation speed per unit area of the surface. The method of determining the rate of spraying of the following (spray rate can also be estimated by the manufacturer):
a) if the laboratory has the appropriate equipment, measure the density of each calibration sample. Acceptable for this purpose, a method for determining the density of homogeneous samples is the division of the sample weight to the volume when the sample volume is measured by immersing it in water, using the principle of Archimedes. Alternate sample volumes may be evaluated by measuring its size, or density can be calculated from the chemical composition, as described in Appendix A [equation (A. 29)]. The accuracy of the measured or calculated density shall be not less than 5%;
b) preparation of the sample surface is carried out in accordance with the recommendations of the device manufacturer or by other suitable method;
c) control parameters of a glow discharge set at 6.2;
d) spray the sample within the time established by the results of formation of a crater etching depth of 20 to 40 microns, registering the total time of spraying;
e) repeat the procedure in listing d) multiple times if the surface area of the sample is large enough, registering the total spraying time for each crater;
f) measure the average depth of each crater optical or mechanical profilometer, measuring not less than four profiles in different directions that cross the center of the crater;
g) absolute speed of spraying:
1) measure the area of at least one crater;
2) expect the atomized volume of each crater by multiplying the square of the spray average depth of sputtering;
3) expect the atomized mass by multiplying the volume sprayed on the density of the sample;
4) expect the dispersal rate for each crater etching as the mass loss divided by the total time of spraying;
5) calculate the average dispersal rate and the standard deviation of the measurements of each crater;
h) for the relative speed of spraying:
1) expect the atomized mass per unit area of the surface for each crater by multiplying the spray depth (crater) on the density of the sample;
2) expect the dispersal rate per unit area of the surface for each crater as the mass of spray per unit area divided by the total time of spraying;
3) choose the sample of comparison (it is recommended that iron or low alloy steel) and measure the average velocity of spraying per unit area for these samples as described above for the calibration samples;
4) expect the relative dispersal rate for each crater as the etching rate of sputtering per unit area divided by the average speed of the spraying unit area of a standard sample;
5) calculate the average relative dispersal rate and the standard deviation of the measurements of each crater.
The profilometer used for the calibration of the depth (the crater) should have an accuracy of at least 5%.
Note — Spray mass can also be determined by weighing the samples before and after spraying. However, this requires the use of weights of high accuracy and uncertainty in such measurements is inferior to the uncertainty of measurement of the depth of the crater.
6.3.5 Measurement of the emission intensity of calibration samples
The measurement of the emission intensity of calibration samples is performed as follows:
a) surface preparation calibration samples is carried out in accordance with the instructions of the instrument manufacturer. If such instructions are not available, you can use abrasive paper grit 220, as a rule, this is sufficient for any monolithic sample. However, you can apply and wet grinding, and then wet samples shall be dried thoroughly by rinsing them with alcohol, and then removing the solvent by a stream of inert gas, such as argon or nitrogen. Be careful not to touch the surface of the sample tube to the gas supply;
b) configure the source settings that are selected in 6.2. Choose a stabilization time of discharge from 50 to 200 C and the integration time of the signals from 5 to 30;
c) measure the radiation intensity of the analyte. Units of measure expressing the intensity doesn’t matter. Frequently used units is the number of counts per second (CPS) or volts (V). Measure each sample at least two times and calculate the average value.
6.3.6 the calculation of the calibration parameters
Performing the calibration calculations are carried out in accordance with the methods established in A. 2 or A. 3 of Annex A.
Note — depending on the type of source, mode of action and the selected calibration samples of the calibration dependence for some elements may be different for samples with different matrix. Distinguish typical cases between the two sets of matrices: one group includes low alloy steel, high alloy steel and brass; the second group — aluminum and zinc-aluminum alloys. This difference has been especially evident in the calibration graphs, the calculation of which included samples from matrices of both groups. This phenomenon is explained by the difference in the output of emission of atoms of the analyte from different matrices well known for a method using glow discharge plasma. However, it can be used special equipment, which is able to minimize this effect. Another solution is to choose from each calibration curve for calibration samples the sample that is most similar to the analyzed samples is usually additional difficulties and requires no special equipment. For example for zinc, when analyzing the zinc-aluminum coating of steel, pieces of brass should be excluded from calibration curve.
6.4 Validation (validation) calibration dependencies (characteristics)
6.4.1 General requirements
To confirm that the calibration dependencies are correctly installed, carry out their test. This process is called validation of the calibration dependencies (see note). It is not necessary to check the calibration every time you analyze a new sample. The transaction confirmation should be used during long-time operation, to check for drift of the instrument during the measurement time, as described in 6.5.
The following two procedures. The first procedure (6.4.2) is performed by using monolithic samples comparison, and the second (6.4.3), using samples comparison with coatings. Since the fabrication process of the samples with coatings is complex, the procedure according to 6.4.3 is not required.
Note — Validation is the confirmation by provision of objective evidence that specific requirements for specific use or application made (standard [12], paragraph 3.8.5). Checking method established in the standard [13] (paragraph 5.4.5) and check the calibration of the equivalent (see note 6.5).
6.4.2 Validation of analytical precision using monolithic samples comparison
a) Choose a suitable number of monolithic samples of comparison to use to check the calibration in accordance with
b) Measure the radiation intensity of analyte in the samples selected for this test, under the same conditions of excitation of glow discharge stabilization time discharge and integration of the signal as in the calibration. At least three independent measurements should be performed on each sample on the newly prepared surface for each measurement.
c) According to the calibration equations compute the average mass fraction of analyte for each sample.
d) the Average value of the mass fraction of analyte, thus measured, should be agreed with known values within the relevant statistical standards of precision. If the differences exceed the allowable, it is necessary to identify the cause and repeat the procedure of calibration.
6.4.3 Validation of measurement accuracy using comparisons of the samples with coatings
a) Follow the manufacturer’s instructions of the instrument in the analysis of the depth profile.
b) Use the same performance parameters of the glow discharge, which was used to establish the calibration dependencies.
c) Spray coating of the reference sample over time, ensuring the complete removal of the coating, and spraying continue to spraying basics.
d) Follow the instructions of the manufacturer of the device to calculate the relationship between intensity and time (quality) and mass percent of the thickness in micrometers (quantitative). Modern software allows devices to automatically compute these relations at the end of each analysis.
e) calculate the mass of the coating in grams per square meter. Coating mass per unit area can be calculated using the theoretical or calculated densities. The difference between the set value of the mass of the coating in the reference sample and found the calculated value must not exceed ±10%.
f) calculate the thickness of the coating. The difference between the set value of the thickness of the coating in the reference material and the estimated value shall be ±5% or less. The difference between the values obtained by chemical analysis of the coating production samples, and the calculated value should be within ±10%.
g) the presence of the Profiler allows you to check the calculated thickness. If installed in the reference sample of the coating thickness, the calculated value and the value obtained using the profilometer, agree within the tolerances given in the procedure for enumeration of f), then the calibration dependencies are acceptable.
h) Counting the average values of the analyte content (% by mass) in the coating and in the base. The calibration dependence are acceptable if the relative accuracy for the mass fraction of the main elements in their content of 1% is not more than ±5% .
i) If the audit revealed discrepancies, repeat the calibration procedure.
When the calibration dependence is properly installed, the accuracy of determination of mass fractions of elements and coating thickness will be provided.
6.5 Verification (testing) the stability of the calibration parameters and drift correction
The analytical signal in modern devices can be prone to displacement (drift) after some time measurements. Even if the device has just been subjected to calibrated and verified, a confirmation is necessary that the calibration dependencies are under control, before measurements of unknown samples for each working day or shift. If the manufacturer of the device did not provide methods to check the calibration, can be applied the following methodology:
a) choose a limited number of homogeneous samples (or reference samples) that will be used to check the stability of the calibration dependencies.
b) measure intensity of analytes for these samples under the same conditions of the glow discharge, the same time stabilization of the discharge and with the same integration time signals, as in the calibration. You must spend at least two independent measurements of each sample when using svejeprigotovlenny surfaces;
c) calculate the average value of the mass fraction of analytes for each sample using the calibration equation;
d) the average value of the mass fraction of analyte, thus measured, should be agreed with known values within the relevant statistical standards of precision. If the difference exceeds the allowable value, is carried out the drift correction in accordance with the instructions of the instrument manufacturer.
It is recommended after the correction of the drift to ensure the accuracy of the calibration dependencies.
Note — Verification (checking) is the confirmation by provision of objective evidence that specified requirements have been fulfilled (the standard [12], paragraph 3.8.4 and compare with the note 6.4.1).
6.6 Analysis of samples
Analysis of samples is carried out in accordance with the procedure in 6.1 and 6.2, using the calibration dependences obtained in accordance with 6.3−6.5.
7 Processing of results
7.1 Quantitative characteristics of profile distribution of the studied parameters on the coating thickness
To assess the distribution profile of the content of the analyte over the thickness is carried out layer-by-layer quantitative analysis a typical example of which is shown in figure 1.
Figure 1 — Distribution of analyte depth electroplating (Zn-Fe) coating on steel
— depth of cover, mm;
— weight analyte, %
Figure 1 — Distribution of analyte depth electroplating (Zn-Fe) coating on steel
7.2 the determination of the total coating mass per unit area
The total mass of the coating per unit area (g/m) for each element calculated using the appropriate algorithms, is given in A. 3 or A. 4, and the method of calculation is given in Appendix C. Carried out the integration of the values of the spray mass per unit area
, was found in A. 20 or A. 27, around the time interval corresponding to the thickness of the coating. The transition from time to the thickness and, conversely, from the thickness to the time spend by the algorithm (see A. 5, Annex A).
Note — Integration (d/m/s) is carried out by a depth profile with respect to time in seconds. This procedure can be included in the software of the device. In this case, the procedure is carried out in accordance with p.3.2 of Annex C.
For major elements, the following recommendations for determining the total (overall) depth, including the thickness of the coating and the transition zone:
a) determine the coating thickness as the depth at which the mass fraction of the main element is reduced to 50% of the maximum value in the coating. The maximum value is the highest mass fraction of the original definition of Zn=84%;
b) the thickness of the transition zone between base metal and coating of the test sample is determined as the difference between the depth at which the mass fraction of the main elements of the coating is reduced to 84% of the maximum value in the coating, and the depth at which the reduction reaches 16% of their maximum values;
c) the total (overall) depth is defined as the sum of the thickness of the coating and the transition zone.
7.3 Determination of the average values of mass fractions of elements
The average value of the mass fraction of each element is calculated by dividing the mass of analyte coating on the sum of the masses of all the elements of the coating.
8 Precision
Evaluation of the precision of the method carried out according to test results obtained in four laboratories for the seven elements, with each laboratory carried out two or more definitions of each element. Used samples and average values of the results are shown in table D. 1 of Annex D. the results Obtained were processed statistically in accordance with the standard [10]. Two or more definitions have been made in the conditions of repeatability as specified in the standard [9], i.e. one operator on the same equipment in identical testing conditions using the same calibration for a minimum period of time. The limit of repeatability was calculated according to the standard [11]. The data obtained are summarized in tables 1 and 2. Graphical representation of the data is given in Appendix D (figures D. 1 and D. 2).
Note — the precision Data presented for test results of coatings on steel deposited by hot dip, in practice mostly depend on the heterogeneity of industrial designs, and not on the measurement method.
Table 1 — Standard deviation of repeatability and limit of repeatability in the determination of coating mass per unit area
| Type of coverage | The standard deviation of repeatability |
The limit of repeatability |
| Electrolytic coating | 0,75 | 2,1 |
| Coating hot dip | 4,5 | 12,6 |
Table 2 — Standard deviation of repeatability and limit of repeatability in percent mass fraction in determining the chemical composition of coatings
| Mass fraction of element, % | The standard deviation of repeatability |
The limit of repeatability |
| Less than 0.1 | 0,006 |
0,017 |
| 1 | 0,03 |
0,084 |
| 10 | 0,2 |
0,56 |
| 99 | 1 |
2,8 |
9 test report
The test report shall contain:
a) all information necessary for identification of the sample;
b) name of organization (laboratory) performing the tests;
c) test method with reference to this standard;
d) the results of the test and the form in which they are expressed;
e) any deviation during the test;
f) details of any operation not specified in this standard and any additional operations that may affect the results.
Annex a (mandatory). Calculation of calibration parameters and equations for quantitative evaluation of depth profiles of
Appendix A
(required)
A. 1 Notation
A. 1.1 Notation used in this Appendix — the atomic concentration of element
in the segment
;
— the area of the crater in the sample
;
— mass fraction of element
in the sample
;
— mass fraction of element
in the segment
of the sample
;
— spraying for the segment
;
element
;
— the intensity of the spectral line
of the element
;
— the segment of the depth profile;
;
— the density of the pure element
;
— the density in the segment
;
— the atomic weight of the element
;
— the thickness of the segment
.
A. 1.2 Symbols used in A. 2 and A. 4, regarding the relative speeds of spray — the value of the intensity of the spectral background at the wavelength
, wt.%;
— given the intensity value of the spectral background at a wavelength of
, %;
— the value of the intensity of the spectral background at the wavelength
;
in the segment
;
— the coefficient determined by the transformed (inverted) value of the emission output of the element
for the spectral lines
and the relative dispersal rate;
sprayed weight per unit area of the element
segment
of the sample M;
— spray rate, expressed as the rate of mass loss per unit area in the sample
;
— spray rate, expressed as the rate of mass loss per unit area in the segment
;
and the reference sample;
;
— the transformed (inverted) value of the output emission element
on spectral lines
;
— the output value of the emission element
on spectral lines
;
is the coefficient expressing the degree of nonlinearity.
A. 1.3 Notation used in A. 3 and A. 5 related to the absolute velocity of the spray — the value of the intensity of the spectral background at the wavelength
expressed in wt.%, multiplied by the rate of spraying;
— given the intensity value of the spectral background at the wavelength
, expressed in wt.%, multiplied by the rate of spraying;
in the segment
;
— the coefficient determined by the transformed (inverted) value of the emission output of the element
for the spectral lines
and the speed of spraying;
sprayed the mass of an element
in the segment
of the sample
;
the dispersal rate or the rate of loss of mass of the sample
;
— spray rate or rate of mass loss in the segment
;
— the reciprocal values of the emission element
on spectral lines
;
— the output value of the emission element
on spectral lines
;
is the coefficient expressing the degree of nonlinearity.
A. 2 calculation of the calibration parameters using the relative velocities of the spray
The calibration dependence is determined by one of the following equations:
or
where — mass fraction of element
in the sample
;
and the reference sample;
— spray rate, expressed as the rate of mass loss per unit area in the sample
;
— spray rate, expressed as the rate of mass loss per unit area in the reference sample;
— the transformed (inverted) value of the output emission element
on the spectral line
(note 1);
— the intensity of the spectral line
of the element
;
— the value of the intensity of the spectral background at a wavelength
, % wt. (can be interpreted as a constant value or as some complex function, given in units of mass fraction, as proposed by the manufacturer);
— given the intensity value of the spectral background at a wavelength
, which is represented in equation (A. 2), in units of mass fraction, is often understood as a «background equivalent concentration» and is interpreted as a constant or a function proposed by the manufacturer (see also note 2);
Note 1 — the converted value of the output emission element
on spectral lines
associated with the magnitude of the issue
by the equation
where the value of the output emission is defined as
where is the intensity value of the spectral background at the wavelength
.
Note 2 — Two designations of spectral background ratio
Equation (A. 1) and (A. 2) can be converted to nonlinear calibration dependencies taking into account the amendments of the second and higher order. An illustration of such a nonlinear calibration dependency (A. 1) and (A. 2) are respectively:
and
where is a correction factor that takes into account the degree of nonlinearity.
These calibration dependence was obtained by regression analysis of the calibration data using method of least squares.
The parameter representing the rate of sputtering per unit area, often used for materials such as low alloy steel. Noticed that some of the calibration samples on the basis of steel the relative velocity of atomization and the correction factors for the speed of the spray close to the unit and is not sensitive to the conditions in the plasma discharge.
Note 3 — the Values of the spectral background in the equations (A. 1) and (A. 2) are not constant, and in varying degrees, depend on the matrix, as given
Note 4 — All available commercial devices manufactured in recent years, to carry out the correction of the background and account for inter-element effects.
A. 3 Calculation of the calibration dependencies using absolute sputtering speeds
The calibration dependence is determined by one of the following equations:
or
where — mass fraction of element
in the sample
;
— spray rate, expressed as the rate of mass loss in the sample
;
— the transformed (inverted) value is output to the emission of the element
for the spectral line
(note 1);
— the intensity of the spectral line
of the element
;
— the value of the intensity of the spectral background at the wavelength
, wt.%, multiplied by the rate of spray (can be interpreted as a constant or some complex function, given in units of mass fraction, multiplied by the rate of spraying of manufacturer of device);
— given the value of the spectral background at the wavelength
, wt.%, multiplied by spray rate, which is given in equation (A. 9).
Note 1 — the reciprocal values of the emission 
to the spectral line
refers to the output value of the issue
as
where the amount of emission is defined as
where is the intensity value of the spectral background.
Note 2 — the Values of the spectral background and
are linked by the following dependence
Equality (A. 8) (A. 9) can be converted to nonlinear calibration dependencies taking into account the amendments of the second and higher order. An illustration of such a nonlinear calibration dependency of the second order equations (A. 8) (A. 9) are, respectively, the following equation:
and
where is the correction factor that takes into account the degree of nonlinearity.
These calibration dependence was obtained by regression analysis of the calibration data using method of least squares.
Note 3 — the Values of the spectral background in the equations (A. 8) (A. 9) are not constant, and in varying degrees, dependent on the matrix (base), as indicated
Note 4 — All available commercial devices manufactured in recent years, to carry out the correction of the background and account for inter-element effects.
A. 4 calculation of the mass fraction of sputtered and mass using relative velocities spraying
A. 4.1 General requirements
The calculation of the mass fraction of elements and the sprayed mass is performed in accordance with different sets of algorithms, as described below, depending on the use of the calibration dependence. However, the end results are equivalent.
A. 4.2 Calculation based on the initial relative velocity spraying
If you have used the calibration dependence is based on equation (A. 1), perform the following steps. For each segment of the depth profile calculated from the calibration based on quantity
. This quantity is called the relative initial velocity of the spray.
Provided that the amount of installed contents of all elements is more than 98%, calculated relative speed of the spraying 
for the depth profile of the sample
using the equation
Mass fraction of the element in the segment
, %, is determined from the equation
where given in percentages.
Total weight 
over a period of time
, determined by equation
A. 4.3 Calculation based on mass fractions of elements
If the calibration was used the calibration dependence is based on equation (A. 2), perform the following steps.
Provided that the amount of installed contents of all elements is greater than 98% calculated mass fraction of the element
in the segment
of the sample
, %, according to the equation
where is equal to
Note — Equation (A. 18) normalizes the sum of all mass fraction to 100%.
If they use non-linear calibration dependence, we replace all of the linear relationship, given in equation (A. 18), the corresponding nonlinear dependencies.
For each depth profile of the segment to calculate the dispersal rate expressed as the rate of mass loss per unit area in the segment
using the equation
For each segment, and corresponds to the segment of time sputtering
depth profile, calculate the mass
, atomized per unit area of the element
using the equation
The total weight 
is determined by the equation
A. 5 Calculation of mass fraction and mass sprayed, using the absolute sputtering speeds
A. 5.1 General requirements
The calculation of the initial mass fraction and the sprayed mass is performed in accordance with different sets of algorithms, as described below, depending on the use of the calibration dependence. However, the end results are equivalent.
A. 5.2 Calculation based on the source speed spray
If you have used the calibration dependence is based on equation (A. 8), perform the following steps.
For each segment of the depth profile calculated from the calibration dependencies for the item
in the segment
.
Provided that the amount of installed contents of all elements is more than 98%, calculate the dispersal rate of the segment of
the depth profile of the sample
using the equation
Mass fraction of the element in the segment
of the sample
, %, determined by equation
The total mass 
over a period of time
, determined from the equation
where is the area of the crater sample
.
A. 5.3 Calculation based on mass fractions of elements
If the calibration was used the calibration dependence according to equation (A. 9), perform the following steps. Provided that the amount of installed contents of all elements is greater than 98% calculated mass fraction of the element in the segment
of the sample
, % mass, according to the equation
where equivalent
Note — Equation (A. 25) normalizes the sum of all the chemical elements mass fraction to 100%.
If they use non-linear calibration dependence, we replace all of the linear relationship, given in equation (A. 25), the corresponding nonlinear dependencies.
For each depth profile of the segment calculate the speed of spraying
according to the equation
For each segment, and corresponds to the segment of time sputtering
depth profile, calculate the mass
of the item
according to the equation
The total weight 
is determined by the equation
A. 6 Calculation of the depth of the spray
A. 6.1 General requirements
The analytical method given in this standard allows to determine the total spray weight of coating and the mass fraction of each element. To determine the depth of the spray it is necessary to know the density of the sprayed material. For the materials considered in this standard, this can be done, knowing the elemental composition of the coating and the density of the pure elements.
Below are two methods of calculating the depth of the spray, which can be used in this method.
A. 6.2 Calculation based on the constancy of atomic volume
For each segment of the depth profile, calculate the density according to the equation
where is the density of a pure element
.
For each segment of the depth profile, calculate the thickness of the segment
according to the equation
Total depth is the sum of all segments.
Although it is not strictly necessary, it is possible to calculate the dispersal rate from surface unit in the segment division 
.
A. 6.3 Calculation using the average density
For each segment of the depth profile calculated atomic percentage
for each element
by the equation
where is the atomic weight of the element
.
For each segment of the depth profile, calculate the density
according to the equation
For each segment of the depth profile, calculate the thickness
by equation (A. 30). Total depth calculated by summing the
in
.
Annex b (informative). The proposed spectral lines to identify elements
The App
(reference)
| Item | Wavelength, nm | The range of definitions % |
Note |
| Zn | 330,26 |
From 0.001 to 100 | - |
| Zn | 334,50 |
From 0.001 to 100 | - |
| Zn | 481,053 |
From 0.001 to 100 | - |
| Al | 172,50 |
From 0.1 to 100 | - |
| Al | 396,15 |
From 0.001 to 100 |
Self-absorption |
| Ni | 231,603 |
From 0.01 to 100 | - |
| Ni | 341,78 |
From 0.001 to 100 |
Weak self-absorption |
| Ni | 349,30 |
From 0.005 to 100 |
Weak self-absorption |
| Pb | 202,20 |
0.001 to 10 | - |
| Pb | 405,87 |
From 0.005 to 100 | - |
| Sb | 206,83 |
From 0.005 to 2 | - |
| Si | 212,41 |
Not defined | - |
| Si | 251,61 |
Not defined | - |
| Si | 288,16 |
From 0.001 to 20 | - |
| Fe | 249,318 |
From 0.01 to 100 | - |
| Fe | 259,94 |
From 0.01 to 100 | - |
| Fe | 271,44 |
From 0.1 to 100 | - |
| Fe | 371,94 |
From 0.005 to 100 |
Weak self-absorption |
| Fe | 379,50 |
From 0.01 to 100 | - |
| Cu | 296,12 |
From 0.01 to 100 | - |
| Cu | 327,40 |
From 0.001 to 5 |
Strong self-absorption |
| |||
Application (reference). Determination of coating mass per unit area
Application
(reference)
C. 1 General requirements
The coating mass per unit area calculated from the quantitative depth profile, which is expressed on the y-axis in g/m/s, and the x-axis is in seconds. All commercial systems of the spectrometer GD-OES have software to calculate the mass of coating per unit area for each individual item. This can be achieved by summing the mass of each depth segment is obtained by using equations (A. 16), (A. 27) (A. 28), depending on the method of calculation. On devices, where possible, the coating mass per unit area can also be calculated from a quantitative depth profile, which is expressed on the y-axis in g/m
/s, and the x-axis is in seconds. The key issue in these calculations is the determination of the area that it is covering. This is especially necessary when the designated element is present in significant quantities in the coating and the base metal. For such cases, we recommend the following two ways.
C. 2 Method 1
Consider an example where the element content in the core material more than in coverage. This case can be attributed to the galvanic zinc coating, an illustration of which is presented in figure C. 1.
Figure C. 1 — Quantitative depth profile versus time, illustrating a method 1 for galvanic zinc coating
1 — Zn;
2 — AI in coverage; 3 — Fe; 4 — Fe in coating; 5 — 95% max Zn content
Figure C. 1 — Quantitative depth profile (g/m/s) vs. time © illustrating a method 1 for galvanic zinc coating
In this example, as an item of interest, consider Fe. Time (the point at which Fe begins to appear from the base metal) corresponds to the time at which the value of the y coordinate for the main part of the coating Zn drops to 95% of the maximum value or to a value corresponding to the inflection point on the curve. After a time
, the Fe content in the coating decreases and reaches zero relative to the Zn profile. Thus, the total content of Fe in the transition zone is equal to the total content of Zn, the corresponding range between the time
and the time curve of the concentration of Zn falls below the detection limit for Zn, multiplied by the ratio of Fe content to the Zn content when the value of the ordinate equal
. Then the total content of Fe in the form of values for the mass per unit area of the coating is determined from the sum of the mass of Fe per unit area of the coating in the transition zone of the profile and Fe, integrated over the entire time to the point
.
Note — an Alternative definition of point may, whenever the controlled elements do not exist in the coverage but are present in the basis. In this case,
can be defined as the time at which these elements are detected for the first time. Nb, Mo and co are examples of such opportunities for controlled elements.
In the case where the covering elements are present at higher mass fractions in the coating than in the base metal, coating mass per unit area will be combined for a range of time from zero to the time at which the value of the point on the ordinate drops to the characteristic in the substrate.
C. 3 Method 2
P.3.1 the Calculation of the depth profile (g/m/s) vs. time (s)
As in the previous case, method 2 is best explained by the example of electroplating zinc (figure C. 2). Time is defined as the time at which the value on the ordinate for the main element of the coverage of Zn is equal to Fe. Over time
this is taken, which corresponds to the total (total) depth as the sum of the thickness of the coating and the transition zone, as defined in 7.2, the procedures of enumeration).
Figure C. 2 — Quantitative depth profile versus time illustrating method 2 for the galvanic zinc coating
1 — Zn;
2 — Fe; 3 — Fe minus Fe in coating; 4 — line, symmetrical line Zn; 5 — 0,854symmetric line Z
Figure C. 2 — Quantitative depth profile (g/m/s) vs. time ©, illustrating method 2 for the galvanic zinc coating
The weight of Fe in the coating per unit area, g/m, calculated using equation*
_______________
* The text of the document matches the original. — Note the manufacturer’s database.
The mass of Fe in the coating per unit area 
where 
;
to
;
— the conversion factor.
The conversion factor is usually calculated as
1-(Fe content, % mass, in coverage)·2/100.
When the mass fraction of iron in the coating is close to 10%, the update factor may also be defined as 55,847/65,37=0,854 to account for the difference in atomic weights between Fe and Zn.
Note — This method can be considered similar to the method of calculation, based on determining the difference between the total Fe content and the summed integral of the difference (Fe — Fe in the coating) in time from 0 to in figure C. 2.
For other elements that were not present in significant mass fractions in the substrate, the coating mass per unit area is calculated as the integral over time from 0 to time .
P.3.2 Calculation of the depth profile in units of mass fraction relative to the depth
This procedure is intended for use in cases where the manufacturer installs the software to automatically calculate the mass of Fe per unit area of the coating, due to the depth profile, which is expressed on the ordinate in units of mass fraction and the abscissa is in units of depth (usually in micrometers) (figure C. 3). An example is given for the galvanic zinc coating and includes the following steps.
Figure C. 3 — Quantitative depth profile expressed in mass fractions of analyte relative to depth, illustrating the method 2 for the galvanic zinc coating
— depth, m;
— mass fraction of analyte, %;
— the width of the transition zone;
the depth corresponding to 50% zinc content plus the width of the transition zone;
the depth at which the mass fraction of Zn and Fe are the same
Figure C. 3 — Quantitative depth profile expressed in mass fractions of analyte relative to depth, illustrating the method 2 for the galvanic zinc coating
Find the thickness at which the mass fraction of Zn is reduced to 84% and 16% of the maximum mass fraction of Zn in the coating, also record the thickness at which it is 50% of maximum. Do the thickness as 84% Zn, 16% Zn and 50% Zn respectively.
Determine the width of the surface section , as the difference on the abscissa between the points 16% Zn and 84% Zn .
Define depth as the point on the abscissa corresponding to 50% of Zn on the ordinate, plus the width of the surface section
. Calculate the mass of coating per unit area from depth zero to depth
for all alloying elements except Fe.
Define depth as the depth at which the mass fraction of Zn and Fe are equal. Expect the total mass per unit area of Fe in the coating depth zero to depth
.
Calculate the mass of Zn in the coating per unit area from depth to depth
. Using the symmetry and the ratio of the masses, convert the mass of zinc per unit area of the coating from the substrate at depth
in the equivalent mass of iron
.
The weight of Fe in the coating per unit area, g/m, is calculated by subtracting the equivalent mass of Fe per unit area of the coating from the total mass of Fe in the coating
where Fe atomic weight/atomic weight of Zn = 55,847/65,37=0,854.
Annex D (informative). Additional information on international cooperative tests
Appendix D
(reference)
The data given in tables 1 and 2 of this standard, was obtained from the results of intelligence tests conducted in 2001 and 2002 for zinc and zinc-aluminum coatings in four laboratories in three countries. A full report on these tests is given in documents N and 38 N 55, can be obtained at the Secretariat of TC 201/SC 8.
The samples and the obtained results of coating mass per unit area, and the content of chemical elements mass fraction in the coatings is given in table D. 1.
Table D. 1. Samples for testing and the results obtained
| N sample | Type of coverage | Coating mass per unit area, g/m |
Chemical composition, % wt. | |||||
| Zn |
Fe | Al | Ni | Si | Pb | |||
| 3 | Zn-Fe (hot-dip galvanizing — HZ and annealing; electroplating — G) |
57 | 89,1 | 10,23 | 0,210 | - | - | - |
| 101 | Zn-Fe (hot-dip galvanizing and annealing; electroplating) |
49,0 | 88,3 | 11,3 | 0,37 | - | - | - |
| 102 | Zn-Fe (hot-dip galvanizing and annealing; electroplating) |
50,7 | 89,5 | 10,05 | 0,38 | - | - | - |
| 103 | Zn-Fe (hot-dip galvanizing and annealing; electroplating) |
49,7 | 90,6 | 9,0 | 0,39 | - | - | - |
| 104 | Zn-Fe (hot-dip galvanizing and annealing; electroplating) |
53,3 | 86,6 | Of 13.03 | 0,37 | - | - | - |
| 4 | Al-Zn (hot dip galvanized) |
91,4 | 42,6 | - | 54,9 | - | 1,29 | - |
| 12 | Zn-Ni (electrolytic) |
Of 17.81 | 86.2 to | - | - | 12,5 | - | - |
| 201 | Zn (hot dip galvanized) |
113 | 99,5 | - | 0,35 | - | - | 0,11 |
| 202 | Zn-Ni (electrolytic) |
44 | 86,7 | - | - | 13,2 | - | - |
| 203 | Zn (hot dip galvanized; Galfan) |
110 | 94,9 | - | 5,1 | - | - | - |
| 204 | Al-Zn (hot dip galvanized; aluzinc) |
81 | 45,4 | - | 53,2 | - | 1,9 | - |
In graph form the resulting inter-laboratory experiment data are presented in figures D. 1 and D. 2. The figures are presented for data analysis of the monolithic specimens, obtained by interlaboratory tests.
Figure D. 1 — the Ratio of coating mass per unit area and standard deviation
Figure D. 1 — the Ratio of coating mass per unit area and standard deviation
Figure D. 2 is a Logarithmic dependence between the total content and the standard deviation of repeatability
Figure D. 2 is a Logarithmic dependence between the total content and the standard deviation of repeatability
App YES (reference). Information about the compliance of the referenced international standards national standards of the Russian Federation (and acting in this capacity inter-state standards)
App YES
(reference)
Table YES.1
| Marking the reference international standard | The degree of compliance | Designation and name of the relevant national standard |
| ISO 14707:2000 | - | * |
| ISO 14284:1996 | IDT | GOST R ISO 14284−2009 «Steel and cast iron. Selection and preparation of samples for the determination of chemical composition" |
| ISO 17925:2004 | IDT | GOST R ISO 17925−2012 «Coatings based on zinc and/or aluminum on steel. Determination of the chemical composition and the mass of coating per unit surface area. Methods: gravimetry, atomic emission spectrometry with inductively coupled plasma and flame atomic absorption spectrometry" |
| * The corresponding national standard is missing. Prior to its adoption, it is recommended to use the translation into Russian language of this international standard. The translation of this international standard is the Federal information Fund of technical regulations and standards. Note — this standard uses the symbol of compliance of the standards: IDT — identical standards. | ||
Bibliography
| [1] | Grimm, W. Spectrochim. Acta 23B, 443 (1968) |
| [2] | Takadoum, J., Pirrin, J. C., PonstoCorbeau, J., Berneron, R. and Charbonnier, J. C. Surf. Interf. Anal., 6,174 (1984) |
| [3] | Takimoto, K., Nishizaka, K., Suzuki, K. and Ohtsubo, T. Nippon Steel Technical Report 33, 28 (1987) |
| [4] | Bengtson, A., Eklund, A. and Saric, A. J. Anal. At. Spectrom., 5, 563 (1991) |
| [5] | Naoumidis, A., Guntur, D., Mazurkiewicz, M., Nickel, H. and Fischer, W. Proceedings of the 3rd User-Meeting «Analytische Glimentladungs-Spektroskopie», p.138, Julich (1990) |
| [6] | Nelis, T. Colloq. Spectrosc. Internl., York (1993) |
| [7] | Payling, R. Specfroscopy, 13, 36 (1998) |
| [8] | EN 10318, Determination of thickness and chemical composition of zinc — and aluminium-based metallic coatings — Routine method |
| [9] | ISO 5725−1, Accuracy (trueness and precision) of measurement methods and results — Part 1: General principles and definitions (ISO 5725−1 Accuracy (trueness and precision) of methods and measurement results. Part 1. General principles and definitions)* |
| _______________ * Official translation of this standard is the Federal information Fund of technical regulations and standards. | |
| [10] | ISO 5725−2, Accuracy (trueness and precision) of measurement methods and results — Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method (ISO 5725−2 Accuracy (trueness and precision) of methods and measurement results. Part 2. The basic method for the determination of repeatability and reproducibility of a standard measurement method)* |
| _______________ * Official translation of this standard is the Federal information Fund of technical regulations and standards. | |
| [11] | ISO 5725−6, Accuracy (trueness and precision) of measurement methods and results — Part 6: Use in practice of accuracy values |
| [12] | ISO 9000:2005, Quality management systems — Fundamentals and vocabulary |
| [13] | ISO/IEC 17025:2005, General requirements for the competence of testing and calibration laboratories |
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UDC 669.14:620.2:006.354 AUX B39 71.040.40 AXTU 0709
Key words: coatings on steel, the basis of zinc, aluminium, chemical composition, thickness, coating mass per unit area of a surface, the method of atomic emission spectrometry, glow discharge
