GOST R 54566-2011
GOST R 54566−2011 Steel. Standard test methods for estimating the depth bezoperatsionnogo layer
GOST R 54566−2011
Group B09
NATIONAL STANDARD OF THE RUSSIAN FEDERATION
STEEL
Standard test methods for estimating the depth bezoperatsionnogo layer
Steel. Standard test methods for estimating the depth of decarburized layer
OKS 77080
AXTU 0709
Date of introduction 2013−01−01
Preface
The objectives and principles of standardization in the Russian Federation established by the Federal law of 27 December 2002 N 184-FZ «On technical regulation», and rules for the application of national standards of the Russian Federation — GOST R 1.0−2004 «Standardization in the Russian Federation. The main provisions"
Data on standard
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 regional standards, referred to in paragraph 3
2 APPROVED AND put INTO EFFECT by the Federal Agency for technical regulation and Metrology dated November 29, 2011 N 651-St
3 this standard is modified in relation to the regional standard ASTM E 1077* «Standard test methods for estimating the depth of decarburization of steel specimens» (ASTM E 1077 «Standard Test Methods for Estimating the Depth of Decarbuirization of Steel Specimens») by modifying its structure to conform with the rules established in GOST 1.5−2001 (subsections 4.2 and 4.3).
________________
* 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 regional standard to conform to GOST R 1.5.
Comparison of the structure of this standard the structure of the specified regional standard is given in Annex YES
4 INTRODUCED FOR THE FIRST TIME
Information about the changes to this standard is published in the annual reference index «National standards», and the 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 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
1 Scope
This standard specifies methods of assessing the average or maximum depth of decarburization in hardened and unhardened steel products. Given the test methods contain methods for the assessment of depth of decarburization of steels irrespective of their chemical composition, the microstructure of the matrix and the cross-sectional shape. Given the following basic techniques:
a) qualifying methods.
b) microscopic methods;
c) methods of measurement of microhardness;
d) methods of chemical analysis.
These methods are designed to detect changes in microstructure, hardness or carbon content at the surface of the steel specimens due to decarburization due to heating at elevated temperatures during hot deformation or heat treatment.
The depth of decarburization is defined as the depth at which the observed homogeneous microstructure, hardness or carbon content, typical for the inner part of the sample.
In case of disputes as an arbitration method, you should use more precise methods of quantitative or linear analysis (and
The results obtained according to the above testing methods can be used to control the quality of the material supplied in accordance with the agreement between the consumer and the manufacturer, for the establishment of allowances for machining, as well as to assess the impact of production technology on the decarburization.
2 Terms and definitions
2.1 the average depth of decarburization (average depth of decarburization) is the mean value of five or more dimensions a total depth of decarburization.
2.2 the average depth of the zone of pure ferrite (average free-ferrite depth): the Average value of five or more measurements of the depth of complete decarburization.
2.3 full decarbonisation of (complete decarburization): Reduction of the carbon content on the surface of a steel specimen to a value below the solubility limit of carbon in ferrite, with the result that the structure consists only of ferrite.
2.4 the depth of the zone of pure ferrite (free-ferrite depth): the Distance along a line perpendicular to the surface of the sample from the surface to this site, the structure of which is not fully ferritic, i.e. contains other products of phase transitions.
Note 1 — the Term «pure ferrite» is also used to refer to isolated globular grains zaevtektoidnoj ferrite in the microstructure of medium carbon steels zaevtektoidnyh.
2.5 the maximum depth of decarburization (maximum depth of decarburization): the Highest measured value of the total depth of decarburization.
2.6 partial decarburization (partial decarburization): Reduction of the carbon content at the surface of a steel specimen to a level that is lower than the carbon content in the inner zone, is not subject to the decarburization, but above the solubility limit of carbon in ferrite at room temperature.
2.7 total depth of decarburization (total depth of decarburization): the Distance along a line, perpendicular to the sample surface, from the surface to such a phase inside the sample, in which the carbon content becomes equal to its content in the steel, i.e. the sum of the depths of complete and partial decarburization.
3 Selection and preparation of samples
3.1 Samples should be collected from those places that are representative of this product. Seat selection and number of samples depend on the nature of the material being tested and are set by agreement between the manufacturer and the consumer of the products.
3.2 Samples for packing trials using measurement of mikrotverdosti on the surface, for example on the device Rockwell, must have a sufficiently small size that they can be appropriately placed on the table of the hardness tester. The surface of the sample should not be subjected to any treatment except removal of scale (if present) using such a method, which does not change the properties of the subsurface of the metal.
3.3 Samples for metallographic techniques or methods of measurement of microhardness, as well as for macroscopic methods qualifying tests shall be cut from the bulk sample perpendicular to the longitudinal axis of the product, the measurements were carried out on the transverse plane. This technique allows to determine the change in decarburization along the contour of the sample.
3.4 For samples with a diameter of about 2.5 cm polishing and study under the cross-section. In the case of larger cross sections to assess changes decarburization in different parts of the surface should produce one or more samples. In figures 1−3 shows a typical schematic of sampling that can be used for larger sections. The scheme of sampling for large cross-sections must be specified in mutual agreement between the manufacturer and the customer.
Figure 1 is a Typical schematic of sampling for round rods of different size
Figure 1 is a Typical schematic of sampling for round rods of different size
Figure 2 — Typical sampling scheme for square bars of different size
Figure 2 — Typical sampling scheme for square bars of different size
Figure 3 — Typical sampling scheme for flat and rectangular blanks of various sizes
Figure 3 — Typical sampling scheme for flat and rectangular blanks of various sizes
3.5 Samples for chemical analysis should be of a sufficient length, so that the mixture withdrawn at regular intervals turning chips meet the requirements of chemical analysis or dimensions subjected to milling surfaces are large enough for holding a spark spectrometric analysis and small enough to place the sample in the holder of the spectrometer.
4 Methods
4.1 Packing methods
4.1.1 Qualifying test are simple, rapid and economical tests designed to separate niebezpiecznych samples from samples with a considerable decarburization. Based on the results of these tests can be used by other test methods.
4.1.2 Hardness on the sample surface.
In the case of heat-treated products, especially in the condition after quenching, the material is subjected to heat treatment, cut a short sample, which is then processed in the same way as this material, or with him. However, this sample is not subjected to release. The scale that is present on the sample surface, remove with a wire brush, blasting glass bead, etc., and then subjected to the hardness measurement on the surface, usually on scale of Rockwell hardness tester. The presence of decarburization is determined by the difference between the hardness on the surface of the sample and the theoretical maximum hardness to carbon content in the investigated steel. This method is most suitable for steels containing approximately less than 0.55% of carbon, but also allows to detect significant decarburization in steels with higher carbon content. The method is not applicable for steels which are not hardened in the hardening, for example for low-carbon steels.
4.1.3 appearance of the cross section of the sample after etching
The presence of decarburization is determined by the presence of a contrast between surface layer and inner part of the sample after etching. Transverse sample can be subjected to grinding and polishing or macrotrading and microtrain. This method is valid to use for samples in the as-rolled, forging, annealing, normalizing or heat treatment. Obesplozhennym surface layer, if present, is usually looks more bright after etching. Appropriate reagents for macrocrania given in ASTM E 340.
4.2 Microscopic methods
4.2.1 Microscopic methods require the fabrication of micro-sections in the cross section, allowing to accurately determine the depth and nature of the decarburization present. For estimating the depth of decarburization can be used several methods. The statistical accuracy of each method varies with number of dimensions.
4.2.2 Microscopic tests usually give satisfactory results when determining suitability of material for intended use, its compliance with technical requirements, as well as for production control, the development or research.
4.2.3 Microscopic methods are most appropriate for measuring the depth of decarburization in sample in the state after rolling, forging, annealing or normalizing. These methods can also be used for heat-treated samples, albeit with lower accuracy of determining the maximum depth of decarburization.
It is also possible to evaluate samples after annealing spheroidizing or cold plastic deformation, however, in these cases, the detection of structural changes due to the decarburization is more difficult than for the structures obtained after hot deformation or annealing.
4.2.4 Measurement of the depth of decarburization is based on the analysis of changes of microstructure at the surface due to changes in the carbon content. The easiest way to estimate the depth of complete decarburization through a clear contrast between a layer of pure ferrite, if present, and the structure inside the sample. The depth of the zone of partial decarburization can best be understood if the zone consists of ferrite and pearlite. If the sample was subjected to annealing steroidozawisimoy, to measure the total depth of decarburization is used to change the content of carbides in the zone of partial decarburization. In the case of heat-treated samples to measure the total depth of decarburization is used nematandani the presence of structures in the zone of partial decarburization. Such measurements generally underestimate the total depth of decarburization. For some high alloy tool steels, steroidozawisimoy subjected to annealing, the depth of decarburization can be estimated by the colour change of the sample after etching. For austenitic steels containing manganese, in the condition after quenching depth corresponding to a certain carbon content, can be determined by changes in microstructure due to decarburization. Examples of decarburization of steels in as-rolled, heat treatment and spheroidizing annealing are shown respectively in figures 4−9.
Figure 4 — an Example of the microstructure of a fully pearlitic alloy steel in the rolled condition, which are not observed visible signs of decarburization. The dark layer on the surface is iron oxide (rolling mill scale)
Figure 4 — an Example of the microstructure of a fully pearlitic alloy steel in the rolled condition, which are not observed visible signs of decarburization. The dark layer on the surface is iron oxide (rolling mill scale) (200, etching with a 2% alcohol solution of nitric acid)
Figure 5 — an Example of the microstructure with partial decarburization (at the surface and near it observed ferrite) in a fully pearlitic alloy steel in the rolled condition
Figure 5 — an Example of the microstructure with partial decarburization (at the surface and near it observed ferrite) in a fully pearlitic alloy steel in the rolled condition (200, etching with a 2% alcohol solution of nitric acid)
Figure 6 — an Example of the microstructure (fully martensitic) heat treated alloy steel, which are not observed visible signs of decarburization
Figure 6 — an Example of the microstructure (fully martensitic) heat treated alloy steel, which are not observed visible signs of decarburization (200, etching with a 2% alcohol solution of nitric acid)
Figure 7 — Example of partial decarburization at the surface of the sample heat-treated alloy steel with a martensitic structure
Figure 7 — Example of partial decarburization at the surface of the sample heat-treated alloy steel with a martensitic structure (200, etching with a 2% alcohol solution of nitric acid)
Figure 8 — an Example of complete decarburization and partial decarburization in heat-treated alloy steel with a martensitic structure. The total depth of decarburization is the sum of the depths of the zones of complete and partial decarburization
Figure 8 — an Example of complete decarburization (pure ferrite zone 1−2) and partial decarburization (dark zone 2−3) in the heat-treated alloy steel with a martensitic structure. The total depth of decarburization is the sum of the depths of the zones of complete and partial decarburization (1−3) (200, etching with a 2% alcohol solution of nitric acid)
Figure 9 — Example of partial decarburization in carbon and tool steel, annealed on globular pearlite. Area of partial decarburization contains less carbide than the matrix, and many carbides are present in the form of pearlite, and not spheroid
Figure 9 — Example of partial decarburization in carbon and tool steel, annealed on globular pearlite. Area of partial decarburization contains less carbide than the matrix, and many carbides are present in the form of pearlite, and not spheroidal particles. (100, etching in 4% alcoholic solution of picric acid)
4.2.5 Polishing samples should be done in a way to eliminate the rounding of their edges. If you do not hold the mount of the samples and their protection from the chamfer, then satisfactory results can be obtained with the use of machines for automatic polishing. You should apply the cloth with a short NAP; polishing abrasive materials with a size of diamond particles less than 1 micron is often unnecessary. If these machines do not exist, or if the specimens are of small size or awkward shape for these machines, the samples should be mounted in jigs or in various tech plastic. When you use some tech plastics can not obtain the desired preservation of edges. For commonly used plastics better preservation of edges achieved by pressing samples of the materials based on epoxy resin. Optimal retention edges provide coatings deposited by electrolytic or chemical means that are recommended in critical cases. Polishing should be done using methods which allow to reveal the true microstructure of the surface layer in accordance with ASTM E 3.
4.2.6 Pickling should be carried out using standard reagents (ASTM E 407), for example alcoholic solutions of nitric or picric acid, chosen on the basis of the evaluation experience of the material. You can also use special reagents, if dictated by the situation. In such cases, should be agreed between manufacturer and user.
4.2.7 In the case of quenched austenitic manganese steel in the surface layer with carbon content below ~0.5% be present of Epsilon-martensite. This structure is best revealed in the initial etching in a 2% alcohol solution of nitric acid for 5 s, and subsequent etching in a 20% aqueous solution of sodium pyrosulphite for ~20 s. After measuring the depth of this layer, the sample can be subjected to aging at a temperature of about 560 °C for 1 h in order to highlight the pearlite at the grain boundaries in the Central zone, where the carbon content exceeds ~of 1.16%. This perlite is revealed by etching alcoholic solution of nitric or picric acid. These conditions are shown in figures 10 and 11.
Figure 10 — an Example the formation of Epsilon martensite in obesplozhennym surface area hardened austenitic manganese steel containing less than 0.5% carbon
Figure 10 — an Example the formation of Epsilon martensite in obesplozhennym surface area hardened austenitic manganese steel containing less than 0.5% carbon (100, etching with a 2% alcohol solution of nitric acid for 5 s, and then a 20% aqueous solution of sodium pyrosulphite for 20)
Figure 11 — Example of a hardened austenitic manganese steel subjected to ageing at 560 °C for 1 h in order to highlight the pearlite at the grain boundaries in those areas where the higher carbon content of 1.16%
Figure 11 — Example of a hardened austenitic manganese steel subjected to ageing at 560 °C for 1 h in order to highlight the pearlite at the grain boundaries in those areas where the higher carbon content of 1.16% (nominal carbon content in the steel is about 1.3%) (50, etching with a 2% alcohol solution of nitric acid)
4.2.8 Measurement of depth of decarburization
4.2.8.1 the depth of the zones of complete and partial decarburization or the total depth of decarburization can be measured by various methods depending on the required accuracy. Measurements may be taken using the ocular insert with a scale (ocular micrometer), screw-micrometer eyepiece with a touch (thread) or a scale placed on the projection screen of frosted glass. Measurements can be made on the image or photos. Measurements can also be performed using image analysis methods. The accuracy of the measuring devices must be defined with an object-micrometer. Methods of calibration of light microscope is described in ASTM E 1951.
4.2.8.2 Optimal magnification used for measurement should be chosen depending on the observed structure. In some cases it is useful to scan the sample at low magnification before measurement. Used increase should be large enough to adequately resolve the structure and achieve the required measurement accuracy and to exclude measurement errors.
4.2.8.3 Before measurement it is necessary to scan the entire surface of the sample at a suitable magnification (magnifications) to ensure that the sample is prepared properly, to assess the uniformity of the presence of decarburization and to establish its nature, i.e. whether it is total or only partial. If there is a full decarburization (pure ferrite), it is necessary to evaluate its uniformity.
4.2.8.4 the Most simple measurement method, sufficient in many cases, is the selection for measurement those areas of the sample that characterize the average and worst conditions of complete and partial decarburization. The depth dimension of these States is carried out using measuring devices described
4.2.8.5 During quality control or research may require measurement of the average depth of total or partial decarburization, or a total depth of decarburization with a higher statistical precision. In such cases, the decarburization can be determined by carrying out several measurements around the contour of the cross section of the sample in randomly selected locations. For these results, we can calculate average values, standard deviations and 95% confidence intervals. The required number of measurements depends on sample size and required accuracy.
4.2.8.6 in studies to define in any place of sample depth, where the microstructure becomes homogeneous and characteristic of its internal microstructure, can be used a method of linear analysis. Lines are drawn parallel to the sample surface, located at a certain distance from each other, and determine the percentage of each structural component is present.
4.2.8.7 If there is an unusually deep local decarburization, for example, associated with the presence of slivers or sunset, the depth of decarburization in the area of these defects should be measured and stated in the test report separately with an explanation of the nature of the observed defect.
4.2.8.8 To determine the depth of decarburization in highly alloyed tool steels, annealed on globular cementite, for example, in high speed steels, used change the color of the etching. The polished sample is etched 4% solution of nitric acid in methyl alcohol for about 60 seconds, until the surface layer becomes bluish-green. The total depth of decarburization is measured at 100to the point where the color changes from bluish-greenish to greenish-brown.
4.3 Method of measurement of microhardness
4.3.1 Method of measurement of microhardness of it requires the preparation of polished micro-sections in cross-section and is most suitable for heat-treated samples with a sufficiently homogeneous microstructure. It is not recommended for samples that contain two structural components with significantly different hardness.
4.3.2 Estimation of total depth of decarburization is based on the change of microhardness depending on the distance from the surface. The total depth of decarburization corresponds to the depth at which the hardness becomes constant and equal to the hardness within the sample. By agreement between the manufacturer and the customer may determine the depth corresponding to a particular hardness value, called the «effective depth of decarburization». This method is best suited for steels with carbon contents below ~0,55%. At higher carbon content the hardness will not change if there is a change of residual carbides, and residual austenite.
4.3.3 sample Preparation is carried out in the same manner as described
4.3.4 Prior to measurement of the hardness to perform the etching, and view samples to select typical areas or specific sites that are of interest in the test method of hardness measurement. When performing hardness measurements should observe the precautions in accordance with subsection 7.12 of the standard [5].
4.3.5 the sample is applied to the number of prints of the microhardness at regular intervals from the surface to the center, using the methods of Copa or Vickers, until then, until a constant hardness in the range of normal statistical variation. These test methods are given in the standard [5].
4.3.6 Method of Copa is more suitable for such tests because the gradient of hardness leads to distortion of the shape of the imprint of the Vickers diagonal perpendicular to the surface. When using an indenter of Copa its long axis must be parallel to the sample surface. Prints of Copa can be located closer to each other than fingerprints Vickers, causing concerns related to the change in hardness values as a result of exposure field deformation from the next print, because of a smaller field of deformation of the imprint of Copa.
4.3.7 Load during the hardness measurement needs to be as large as possible to minimize the measurement uncertainty of the diagonal and eliminate the problems associated with the use of low loads. Should be possible to avoid the use of loads below 25 grams.
4.3.8 Distance between fingerprints shall not be less than 2.5 times the length of the diagonal in the direction perpendicular to the surface, i.e. in the transverse direction. If the required measurement, you can produce on the nearby parallel transverse lines.
4.3.9 to determine the total depth of decarburization or the effective depth, it is necessary to perform a complete cycle of measurements on the transverse lines from the surface to the inner part of the sample. In order to minimize the complexity of the test, you can use partial measurements on the transverse lines on the basis of the observed microstructure.
4.3.10 Measurement of only one of the transverse lines allow to determine the total or the effective depth of decarburization in only one place. To achieve greater statistical precision in determining these values, you can make multiple partial measurements on the transverse lines in areas selected on the basis of the observed microstructure, and then calculate the average value.
4.4 Methods of chemical analysis
4.4.1 Application of methods of chemical analysis is limited to samples having a simple uniform, based on the analysis of lathe shavings, taken at different depths at specified intervals, or chips, obtained after milling intervals.
4.4.2 Methods of chemical analysis provide direct measurement of carbon concentration as a function of depth. These methods are applicable for steel of any composition and microstructure, but have limitations related to the shape of the sample. These methods are usually used only for research purposes. Measurements taken by these methods usually show higher values of total depth of decarburization than the other methods.
4.4.3 incineration
4.4.3.1 using this method, the sample is subjected to grinding or milling at regular intervals to a preset depth and analyze chips on the carbon content using standard analytical methods. Application of the method is limited to simple shapes of the cross section of the sample, such as a round or flat rental. Samples with high hardness should be high tempering (but not annealing) at 600 °C — 650 °C, which allows you to use cutting.
4.4.4 Round bars in front of the lathe must be accurately centered. It is recommended that dry machining. Before treatment, remove the surface scale. When milling flat samples should be avoided when machining corners. The mass of the chip should be sufficient to perform accurate analysis and re-control if it proves necessary.
4.4.5 the Total depth of decarburization is defined as the depth at which achieved a carbon content equal to its content in the sample within the accuracy of the method of analysis. A more detailed description of this method of analysis is given in ASTM E 350.
4.4.6 Method for atomic emission spectrometric analysis
4.4.7 using this method, the sample is polished to a certain depth, and its surface is subjected to atomic-emission spectrometric analysis of carbon using vacuum emission spectrometer. The application of this method is limited to flat surfaces.
4.4.8 Prior to the initial grinding should remove the surface scale. The sample is polished at regular intervals until you achieve the specified depth values. Depth measurement after each grinding is performed using a micrometer.
4.4.9 After each grinding surface is subjected to atomic-emission spectrometric analysis, and determine the carbon content. The subsequent atomic emission spectrometric analysis should not be carried out in the same places as the previous one, and the analysis should avoid the corner sections. The method of analysis is given in ASTM E 415.
4.4.10 Total depth of decarburization corresponds to a depth where the carbon content becomes constant and equal to its content in the sample within the accuracy of the method of analysis.
5 test report
5.1 the test report shall include the following information:
5.1.1 sample Number, melting, party, etc.
5.1.2 the Number of specimens and place them cut.
5.1.3 the Method used for measurement of decarburization, and the relevant test conditions, e.g. increase, the reagent for etching, the type of indenter and the load.
5.1.4 For the microscopic methods should specify the depth of complete decarburization, or the total depth of decarburization, or both for average and worst conditions. Specify the depth of decarburization observed in the area the presence of the defect, and the nature of the defect. If the customer requires information about decarburization in the corner areas, then this should be noted.
5.1.5 If the method was used to measure the microhardness, it should give overall or effective (with the criterion for hardness) depth of decarburization.
5.1.6 If you have used the method of chemical analysis, specify the total depth of decarburization and the method used.
5.1.7 If you use the methods of linear analysis, measurement of microhardness and chemical analysis, on the basis of the agreement between the manufacturer and the consumer as a desirable, or necessary information may be given to the dependence of the data obtained from depth.
5.1.8 All relevant tests of the agreement between the manufacturer and the customer should be documented.
6 Precision and bias
6.1 the Qualifying test
6.1.1 Qualifying test allow to determine whether production requirements («passes» or «fails»), and used for the purpose of saving time. In conditions of very careful monitoring for reasonably accurate estimates a total depth of decarburization is possible to use a method of measurement of mikrotverdosti on the surface. Method macrocrania cannot be used to obtain reliable estimates of depth of decarburization.
6.2 Microscopic methods
6.2.1 the Use of the method is simple scan to identify sites that seem typical or worst, it may lead to some error. Unsatisfactory preparation of sample, such as a bad preservation of edges can reduce the measurement accuracy. The depth of complete decarburization can usually be estimated more accurately than the depth of partial decarburization, or the total depth of decarburization.
6.2.2 In the case of microscopic dimensions based on the determination of the average values for a set of measurements carried out on randomly selected plots, accuracy and precision increase with increasing number of dimensions. When 20 or more measurements of the depth of decarburization can be determined with a precision of 0.025 mm and a relative accuracy of 10% to 20%. Estimation of the depth of complete decarburization (i.e., the depth of pure ferrite) are more accurate and more reproducible than estimates of the depth of partial decarburization, or a total depth of decarburization.
6.2.3 any measurement can be obtained several different values for samples taken from different parts of the products, even if these sites are located next to each other.
6.2.4 the Accuracy of estimates of total or effective decarburization depth in a given location by measuring the microhardness is usually in the range of 0.025 mm. However, due to the fact that measurements are performed on one or a few phases, these measurements may be atypical for the entire sample.
6.2.5 When using a chemical analysis of the chips obtained by intermittent turning or milling, the results are representative of the entire sample, as the chips are removed from significant surface area. Accuracy is reduced if the layers turning chips were not concentric with the diameter of the rod, or if the layers milling chips was parallel to the surface.
6.2.6 When using intermittent spectrometric analysis of each time is determined by the carbon content in the plot with a diameter of about 5 mm and a depth of about 1 mm. This provides sufficient accuracy, but not as high as when using the method of intermittent turning or milling.
App YES (reference). Comparison of the structure of this standard the structure applied in this regional standard
App YES
(reference)
Table YES.1
| The structure of this standard |
The structure of the regional standard |
| 1 Scope |
1 Scope |
| 4 overview of methods | |
| 2 Terms and definitions |
3 Terminology |
| 3 Selection and preparation of samples | 5 the Meaning and use |
| 6 Sampling | |
| 4 Methods |
7 Method |
| 5 test report |
8 test report |
| 6 Precision and bias |
9 Precision and accuracy |
| App YES a Comparison of the structure of this standard the structure applied in this regional standard |
|
| Bibliography |
2 Normative references |
Bibliography
| [1] | ASTM E 340−01 | Methods macrocrania of metals and alloys |
| (ASTM E 340−01) | Test Method for Macroetching Metals and Alloys | |
| [2] | ASTM E 3−01 | The method of preparation of samples metallografika |
| (ASTM E 3−01) | Guide for Preparation of Metallographic Specimens | |
| [3] | ASTM E 407−01 | Methods microstripline of metals and alloys |
| (ASTM E 407−01) | Practice for Microetching Metals and Alloys | |
| [4] | ASTM E 1951−01 | Manual calibration of eyepiece grids and magnification light microscope |
| (ASTM E 1951−01) | Guide for Calibrating Reticals and Light Microscope Magnificatons | |
| [5] | ASTM E 384−01 | Method of measurement of microhardness of materials |
| (ASTM E 384−01) | Test Method for Microindentation Hardness of Materials | |
| [6] | ASTM E 350−05 | Methods of chemical analysis of carbon steel, low alloy steel, silicon electrical steel, cast iron and wrought iron |
| (ASTM E 350−05) | Test Methods for Chemical Analysis of Carbon Steel, Low-Alloy Steel, Ingot Iron, and Wrought Iron | |
| [7] | ASTHMA 415−06 | Methods of atomic emission vacuum spectrometric analysis of carbon and low alloy steel |
| (ASTM E 415−06) | Test Method for Optical emission Vacuum Spectrometric Analysis of and Low-Alloy Steel |
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UDC 669.14:620.2:006.354 OKS 77080 B09 AXTU 0709
Keywords: steel, carbon, decarburization, ferrite, microhardness
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