GB/T 4324.2-2023Methods for chemical analysis of tungsten—Part 2:Determination of bismuth and arsenic contents (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document is Part 2 of GB/T 4324 "Tungsten Chemical Analysis Methods". GB/T 4324 has released the following parts.

---Part 1. Determination of lead content by flame atomic absorption spectrometry;

---Part 2. Determination of bismuth and arsenic content;

---Part 3. Determination of tin content by hydride atomic absorption spectrometry;

---Part 4. Determination of antimony amount by hydride atomic absorption spectrometry;

---Part 6. Determination of iron content by phenanthroline spectrophotometry;

---Part 7. Determination of cobalt content by inductively coupled plasma atomic emission spectrometry;

---Determination of nickel content by inductively coupled plasma atomic emission spectrometry, flame atomic absorption spectrometry and diacetyl oxime gravimetric method;

---Part 9. Determination of cadmium amount by inductively coupled plasma atomic emission spectrometry and flame atomic absorption spectrometry;

---Part 10. Determination of copper content by flame atomic absorption spectrometry;

---Part 11. Determination of aluminum content by inductively coupled plasma atomic emission spectrometry;

---Part 12. Determination of silicon content by chloride-molybdenum blue spectrophotometry;

---Determination of calcium content by inductively coupled plasma atomic emission spectrometry;

---Part 14. Gravimetric method for determining the amount of residue after chlorination volatilization;

---Determination of magnesium content by flame atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry;

---Part 16. Gravimetric method for determination of ignition loss;

---Part 17. Determination of sodium content by flame atomic absorption spectrometry;

---Part 18. Determination of potassium content by flame atomic absorption spectrometry;

---Part 19. Determination of titanium content by diantipyrine methane spectrophotometry;

---Part 20. Determination of vanadium content by inductively coupled plasma atomic emission spectrometry;

---Part 21. Determination of chromium content by inductively coupled plasma atomic emission spectrometry;

---Part 22. Determination of manganese content by inductively coupled plasma atomic emission spectrometry;

---Part 23. Determination of sulfur content by combustion conductivity method and high-frequency combustion infrared absorption method;

---Part 24. Determination of phosphorus content by molybdenum blue spectrophotometry;

---Part 25. Determination of oxygen content by pulse heating inert gas melting-infrared absorption method;

---Part 26. Determination of nitrogen content by pulse heating inert gas melting-thermal conductivity method and Nessler reagent spectrophotometry;

---Part 27. Determination of carbon content by high-frequency combustion infrared absorption method;

---Part 28. Determination of molybdenum content by thiocyanate spectrophotometry.

This document replaces GB/T 4324.2-2012 "Methods for chemical analysis of tungsten - Part 2: Determination of bismuth content. Hydride atomic absorption spectrometry Method" and GB/T 4324.5-2012 "Methods for chemical analysis of tungsten - Part 5: Determination of arsenic content by hydride atomic absorption spectrometry", and Compared with GB/T 4324.2-2012 and GB/T 4324.5-2012, in addition to structural adjustments and editorial changes, the main technical changes are as follows:

a) Change the lower limits of the determination range of bismuth and arsenic content from 0.00003% and 0.00005% to 0.00001% respectively (see Section 1 Chapter, Chapter 1 of GB/T 4324.2-2012, Chapter 1 of GB/T 4324.5-2012);

b) The detection method was changed from hydride atomic absorption spectrometry to atomic fluorescence spectrometry (see Chapter 4, GB/T 4324.2- Chapter 2 of 2012, Chapter 2 of GB/T 4324.5-2012);

c) Changes to "reagents or materials" (see Chapter 5, Chapter 3 of GB/T 4324.2-2012, Chapter 3 of GB/T 4324.5-2012);

d) "Instruments and equipment" have been changed (see Chapter 6, Chapter 4 of GB/T 4324.2-2012, Chapter 4 of GB/T 4324.5-2012);

e) Added sample requirements for tungsten powder, tungstic acid, tungsten trioxide, blue tungsten, violet tungsten, ammonium metatungstate and ammonium paratungstate (see 7.1, 7.3 and 7.5);

f) Changed the "Test Procedure" (see Chapter 8, Chapter 6 of GB/T 4324.2-2012, Chapter 6 of GB/T 4324.5-2012);

g) The precision of the determination of bismuth and arsenic content was changed, and the allowable difference was changed to reproducibility (see Chapter 10, GB/T 4324.2-2012 Chapter 8, Chapter 8 of GB/T 4324.5-2012).

Introduction

Tungsten and tungsten alloys are widely used in mechanical processing, metallurgy, mining, electronic telecommunications, etc. due to their high melting point, high specific gravity, and high hardness.

Construction industry, weapons industry, aerospace and other fields. GB/T 4324 aims to establish a complete, feasible and adaptable set of The method standard for chemical composition analysis for the production and trade needs of tungsten products consists of 27 parts.

---Part 1. Determination of lead amount by flame atomic absorption spectrometry. The purpose is to establish a method for determining lead content.

---Part 2. Determination of bismuth and arsenic content. The purpose is to establish a method for the determination of bismuth and arsenic content.

---Part 3. Determination of tin content by hydride atomic absorption spectrometry. The purpose is to establish a method for determining tin content.

---Part 4. Determination of antimony amount by hydride atomic absorption spectrometry. The purpose is to establish a method for determining antimony content.

---Part 6. Determination of iron content by phenanthroline spectrophotometric method. The purpose is to establish a method for determining iron content.

---Part 7. Determination of cobalt content by inductively coupled plasma atomic emission spectrometry. The purpose is to establish the determination of cobalt content method.

---Determination of nickel content by inductively coupled plasma atomic emission spectrometry, flame atomic absorption spectrometry and diacetyl oxime gravimetric method.

The purpose is to establish a method for determining nickel content.

---Part 9. Determination of cadmium amount by inductively coupled plasma atomic emission spectrometry and flame atomic absorption spectrometry. The purpose is To establish a method for determining cadmium content.

---Part 10. Determination of copper content by flame atomic absorption spectrometry. The purpose is to establish a method for measuring copper content.

---Part 11. Determination of aluminum content by inductively coupled plasma atomic emission spectrometry. The purpose is to establish the determination of aluminum content method.

---Part 12. Determination of silicon content by chloride-molybdenum blue spectrophotometry. The purpose is to establish a method for determining silicon content.

---Determination of calcium content by inductively coupled plasma atomic emission spectrometry. The purpose is to establish a method for determining calcium content.

---Part 14. Gravimetric method for determining the amount of residue after chlorination volatilization. The purpose is to establish the determination of the amount of residue after chlorination volatilization method.

---Determination of magnesium content by flame atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry. The purpose is to establish the iron content Quantity measurement method.

---Part 16. Gravimetric method for determination of ignition loss; the purpose is to establish a method for the determination of ignition loss.

---Part 17. Determination of sodium content by flame atomic absorption spectrometry. The purpose is to establish a method for determining sodium content.

---Part 18. Determination of potassium content by flame atomic absorption spectrometry. The purpose is to establish a method for determining potassium content.

---Part 19. Determination of titanium content by antipyrine methane spectrophotometry. The purpose is to establish a method for measuring titanium content.

---Part 20. Determination of vanadium content by inductively coupled plasma atomic emission spectrometry. The purpose is to establish the determination of vanadium content method.

---Part 21. Determination of chromium content by inductively coupled plasma atomic emission spectrometry. The purpose is to establish the determination of chromium content method.

---Part 22. Determination of manganese content by inductively coupled plasma atomic emission spectrometry. The purpose is to establish the determination of manganese content method.

---Part 23. Determination of sulfur content by combustion conductivity method and high-frequency combustion infrared absorption method. The purpose is to establish the determination of sulfur content method.

---Part 24. Determination of phosphorus content by molybdenum blue spectrophotometry. The purpose is to establish a method for determining phosphorus content.

---Part 25. Determination of oxygen content. Pulse heating inert gas melting-infrared absorption method. The purpose is to establish a method for measuring oxygen content.

---Part 26. Determination of nitrogen content by pulse heating inert gas fusion-thermal conductivity method and Nessler reagent spectrophotometry. The purpose is to establish Method for determination of nitrogen content.

---Part 27. Determination of carbon content by high-frequency combustion infrared absorption method. The purpose is to establish a method for measuring carbon content.

---Part 28. Determination of molybdenum content by thiocyanate spectrophotometry. The purpose is to establish a method for determining molybdenum content.

1 Scope

This document describes methods for the determination of bismuth and arsenic in tungsten and tungsten alloys.

This document applies to the bismuth and arsenic content in tungsten powder, tungsten acid, tungsten strips, tungsten trioxide, blue tungsten, violet tungsten, tungsten carbide, ammonium metatungstate, and ammonium paratungstate. Determination. The measurement range (mass fraction) is 0.00001%~0.020%.

2 Normative reference documents

The contents of the following documents constitute essential provisions of this document through normative references in the text. Among them, the dated quotations For undated referenced documents, only the version corresponding to that date applies to this document; for undated referenced documents, the latest version (including all amendments) applies to this document.

GB/T 6682 Specifications and test methods for water used in analytical laboratories

GB/T 8170 Numerical rounding rules and expression and determination of limit values

GB/T 17433 Basic terminology for chemical analysis of metallurgical products

3 Terms and definitions

The terms and definitions defined in GB/T 17433 apply to this document.

4 Principles

Tungsten powder, tungsten strips, blue tungsten, and tungsten carbide (fine and medium particles) are decomposed with hydrogen peroxide and sodium hydroxide; tungsten trioxide, tungstic acid, ammonium paratungstate, and metatungsten Ammonium acid is decomposed with sodium hydroxide; violet tungsten and tungsten carbide (coarse particles) are burned into tungsten trioxide and then decomposed with sodium hydroxide. Use citric acid to complex tungsten in In hydrochloric acid medium, thiourea is used to eliminate the interference of impurity elements such as titanium and tin, ascorbic acid is used to pre-reduce bismuth and arsenic, and titanium trichloride is used to reduce pentavalent arsenic to Trivalent, bismuth and arsenic are reduced to hydrides by potassium borohydride, and the fluorescence intensity of bismuth and arsenic is measured with an atomic fluorescence spectrometer.

5 Reagents or materials

Unless otherwise specified, use only analytically pure reagents.

5.1 Water, GB/T 6682, Level 2.

5.2 Hydrogen peroxide (rho=1.10g/mL), excellent grade pure.

5.3 Nitric acid (rho=1.42g/mL), excellent grade pure.

5.4 Hydrochloric acid (rho=1.84g/mL), excellent grade pure.

5.5 Hydrochloric acid (1 4).

5.6 Hydrochloric acid (1 99).

5.7 Sodium hydroxide solution (100g/L). Weigh 100g of sodium hydroxide and dissolve it in 1000mL of water.

5.8 Citric acid solution (500g/L). Weigh 500g of citric acid and dissolve it in 1000mL of water.