GOST 16882.2-71
GOST 16882.2−71 Silver-copper-phosphorus solders. Methods for determination of phosphorus, lead, iron and bismuth (with Amendments No. 1, 2)
GOST 16882.2−71*
Group B59
STATE STANDARD OF THE USSR
SILVER-COPPER-PHOSPHORUS SOLDERS
Methods for determination of phosphorus, lead, iron and bismuth
Silver-copper-phosphorus solders. Methods for determination
of phosphorus, lead, iron and bismuth content
AXTU 1709
Date of introduction 1972−07−01
The decision of the State standards Committee of the USSR Council of Ministers dated 9 April 1971 N 713 introduction installed with 01.07.72
Proven in 1985 by the Resolution of Gosstandart from
_______________
** Expiration removed by Protocol No. 5−94 of the Interstate Council for standardization, Metrology and certification (I & C N 11/12, 1994). — Note the manufacturer’s database.
* REVISED (July 1986) with Amendments No. 1, 2 approved in March 1981, February 1985 (IUS 6−81, 5−85).
This standard applies to silver-copper-phosphorus solders and sets photocolorimetric (when the mass fraction of phosphorus from 0.5 to 5.0%) and spectral (at a mass fraction of phosphorus from 0.5 to 1.5%) methods for determination of phosphorus and the spectral method for determination of lead, iron and bismuth (in mass fraction of lead from 0.01 to 0.3 percent; iron from 0.01 to 0.2%; bismuth from 0.001 to 0.02%).
(Changed edition, Rev. N 1).
1. GENERAL REQUIREMENTS
1.1. General requirements for methods of analysis GOST 22864−83.
2. PHOTOCOLORIMETRIC METHOD FOR THE DETERMINATION OF PHOSPHORUS
2.1. The essence of the method
The method is based on the photocolorimetric determination of phosphorus in the yellow coloration of phosphorus-vanadium-molybdenum complex.
2.2. Apparatus, reagents and solutions
Photoelectrocolorimeter.
Nitric acid GOST 4461−77 diluted 1:1.
Hydrochloric acid by the GOST 3118−77, diluted 1:1.
Ammonium undeviatingly meta GOST 9336−75, 0,25% solution; prepared as follows: 2.5 g of reagent was dissolved in 500 cmof hot water. After cooling, add 30 cm
diluted 1:1 nitric acid, made up to 1 DM
with water and stirred.
Ammonium molybdate according to GOST 3765−78, solution; is prepared as follows: 50 g of salt dissolved in 1 DMof water.
A standard sample.
2.3. Analysis
The sample analyzed alloy 0.05 g (take three parallel sample) and three sample standard sample of 0.05 g was placed into cups with a capacity of 100 cmand dissolved in 5 cm.
of nitric acid diluted 1:1. After dissolution of the alloy solution was evaporated to a syrupy state, add 5 cm
diluted 1:1 hydrochloric acid and evaporated again. Then dilute the solution to 25 cm
of water and heated to enlightenment. After cooling, the solution was filtered in a volumetric flask with a capacity of 100 cm
. The precipitate of silver chloride washed with cold water. Then to the solution with constant stirring injected 2 cm
of concentrated nitric acid, 10 cm
vadeevaloo ammonium, 10 cm
molibdenovogo ammonium after 1 min the solution was adjusted to the mark with water and mix. Absorbance is measured on a photoelectrocolorimeter with a blue light filter (transmittance 460 nm) in a cuvette with a layer thickness of 10 m
M.
2.2, 2.3. (Changed edition, Rev. N 1).
2.4. Calculation of results of analysis
2.4.1. Mass fraction of phosphorus () in percent is calculated by the formula
where a — optical density of test solution;
— optical density of standard solution;
— the phosphorus content in the master alloy, in %.
2.4.2. Allowable absolute discrepancies in the results of parallel measurements at a confidence probability of 0.95 should not exceed 0.15%.
(Changed edition, Rev. N 2).
3. SPECTRAL METHOD OF DETERMINATION OF PHOSPHORUS, LEAD, IRON AND BISMUTH
3.1. The essence of the method
The method is based on measuring pucherani analytical lines of the elements in the arc spectrum. Communication pucherani concentration is set to the calibration graph, built on a series of standard samples.
The electrodes were applied to the rods of the analyzed alloy.
3.2. Apparatus, reagents and solutions
Quartz spectrograph medium dispersion.
The generator is activated the arc AC.
Microphotometer.
Clips for electrodes with forced cooling.
Photographic plates of the spectral type I sensitivity 5−6 units for wavelength 2500 .
Photographic plates of type II, the sensitivity of 15−16 units.
Standard samples of the enterprise.
N 1 the developer and fixer according to GOST 10691.0−84, GOST 10691.1−84.
3.3. Preparation for assay
Samples and standard samples should be in the form of two cast rods with a diameter of 6 mm and length 20−30 mm., the Ends of the rods sharpened to a hemisphere or a truncated cone with ground diameter of 1.5−1.7 mm.
For removal of surface contamination of the sample is boiled in hydrochloric acid, diluted 1:1, for 3 min, washed with water and dried.
3.2, 3.3. (Changed edition, Rev. N 1, 2).
3.4. Analysis
3.4.1. Determination of phosphorus
Photographing spectra is produced when the width of the slit of a spectrograph 0.015 mm, the distance between the electrodes is 1.5 mm, the strength of the arc current is 5A, the time of the preliminary firing a 30 second exposure time 45 s. the Interelectrode gap is set by the template. Electrodes serve as cast members. The spectra are photographed on photographic plates of the spectral type I. Together with the study samples on the same plate photographed spectra of standard samples analyzed grade alloy.
The spectra are photographed, subject to the terms selected in the following sequence: each sample is removed twice, and then the electrodes are adjusted and the process repeated. For each sample and the standard sample receive four parallel spectrogram.
Photographic plates showing for 4 min at developer temperature of 18−20 °C. the Shown plate is rinsed in water, fixed, washed in running water and dried.
3.4.2. Determination of lead, iron and bismuth
Photographing spectra is carried out at a slit width of the spectrograph 0.01 mm, distance between electrodes of 1.5 mm, a current of 5 A, the time of the preliminary firing 5 C, exposure time 10 s. the Interelectrode gap is set by the template.
The spectra are photographed on photographic plates of type II.
Together with the analyzed samples on the same plate photographed spectra of standard samples analyzed grade alloy.
A photographic plate showing for 2−4 min at developer temperature of 18−20 °C. the Shown plate is rinsed in water, fixed, washed in running water and dried.
3.4.1,
3.5. Processing of the results
3.5.1. Wavelength of analytical spectral lines is given in the table.
| Define item |
Wavelength of lines of the designated element, nm |
Item alignment |
The wavelength of the line item comparisons, nm |
| Phosphorus | 255,49 |
Silver | 257,57 |
| Iron | 259,94 |
Background | - |
| Lead | 283,31 |
« | - |
| Bismuth | 306,72 |
« | - |
Determination of the mass fraction of the elements are by the method of «three standards» with the objective photoretrieval. Build calibration graphs for each of the element. On the y-axis delay value difference pucherani line of the element and element comparison, and the abscissa shows the values of the logarithms of the concentrations of standard samples.
With the help of calibration curve by the known values of the difference of pochernenija find the contents of the analyzed element in the sample.
3.5.2. The convergence of the results of parallel measurements is characterized by the relative standard deviation , is equal to 0.06 in the determination of phosphorus and 0.08 in the determination of lead, iron and bismuth.
3.5.3. The final result of the analysis be the arithmetic mean of three parallel measurements obtained on the three spectrograms, provided
where 
least the result of the parallel measurements;
— relative standard deviation describing repeatability of measurements;
— the arithmetic mean calculated from
parallel measurements (
3).
3.5−3.5.3. (Changed edition, Rev. 1, 2).
