GB/T 26725-2023Ultrafine tungsten carbide powder (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 replaces GB/T 26725-2011 "Ultrafine Tungsten Carbide Powder". Compared with GB/T 26725-2011, this document except for structural adjustments In addition to editorial changes, the main technical changes are as follows.

a) The classification has been changed (see Chapter 4, 3.1 of the 2011 edition);

b) Removed the requirement for average particle size (see 3.3 of the 2011 version);

c) The specific surface area requirements of the product have been changed (see 5.1, 3.3 of the 2011 edition);

d) Added requirements for the content of As, Bi, Cd, Co, Cu, Mn, Ni, P, Pb, Sb, Sn, and Ti (see 5.2);

e) The total carbon content and free carbon content of the product have been changed (see 5.3, 3.3 of the 2011 version);

f) Changed the oxygen content requirements of products (see 5.4, 3.3 of the 2011 version);

g) The test method for chemical composition has been changed (see 6.2, 4.1 of the 2011 edition);

h) The test method for total carbon content has been changed (see 6.3, 4.2 of the 2011 edition);

i) Added the material of the outer packaging barrel (see 8.2).

1 Scope

This document stipulates the product classification, technical requirements, test methods, inspection rules, marking, packaging, transportation, storage, and follow-up of ultrafine tungsten carbide powder. line documents and order form contents.

This document is applicable to the production of ultrafine tungsten carbide powder for powder metallurgy products such as cemented carbide.

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 4324.17 Methods for chemical analysis of tungsten Part 17: Determination of sodium content Flame atomic absorption spectrometry

GB/T 4324.18 Methods for chemical analysis of tungsten Part 18: Determination of potassium content Flame atomic absorption spectrometry

GB/T 4324.23 Methods for chemical analysis of tungsten Part 23: Determination of sulfur content Combustion conductivity method and high-frequency combustion infrared absorption method

GB/T 4324.24 Methods for chemical analysis of tungsten Part 24: Determination of phosphorus content Molybdenum blue spectrophotometry

GB/T 4324.25 Methods for chemical analysis of tungsten Part 25: Determination of oxygen content Pulse heating inert gas melting-infrared absorption method

GB/T 5124.2 Chemical analysis method for cemented carbide - Determination of insoluble (free) carbon content by gravimetric method

GB/T 5314 Powder sampling method for powder metallurgy

GB/T 19587 Determination of specific surface area of solid materials by gas adsorption BET method

JB/T 6647 Gas volumetric method for determination of total carbon content in carbides

YS/T 559 Tungsten emission spectrum analysis method

3 Terms and definitions

There are no terms or definitions to be defined in this document.

4 Product categories

The products are divided into five grades: FWC001, FWC002, FWC003, FWC004 and FWC005 according to their specific surface area.

5 Technical requirements