GB/T 4295-2019Tungsten carbide powder (English PDF)

Foreword

This Standard was drafted as per the rules specified in GB/T 1.1-2009.

This Standard replaced GB/T 4295-2008 Tungsten Carbide Powder. Compared with GB/T 4295-2008, the major technical changes of this Standard are as follows besides the editorial modifications:

--- clarify that "this standard is applicable to tungsten carbide powder with an average particle size no less than 0.6µm for the production of cemented carbide and other powder metallurgy products" (see Clause 1 of this Edition; Clause 1 of the 2008 Edition);

--- Modify the product designation; and divide tungsten carbide powder into 18 designations according to the average particle size (see 3.1 of this Edition; 3.1 of the 2008 Edition);

--- Increase the content requirements of impurities, such as As, Bi, Cd, Co, Cr, Cu, Mn, Ni, P, Pb, Sb, Sn, Ti, V; and increase the content requirements of impurities, such as Ca, Fe, Mg, Mo, S, Si (see 3.2 of this Edition; 3.2 of the 2008 Edition);

--- Add specific surface area requirements for three designations of FWC06-07, FWC07-08, and FWC08-10; modify the requirements for free carbon content, combined carbon content and oxygen content of some designations of tungsten carbide powder (see 3.3 of this Edition; 3.3 of the 2008 Edition).

1 Scope

This Standard specifies the requirements, test methods, inspection rules, marking, packaging, transportation, storage, quality certificates and purchase orders (or contracts) for tungsten carbide powder.

This Standard applies to tungsten carbide powder with an average particle size no less than 0.6µm for the production of cemented carbide and other powder metallurgy products.

2 Normative References

The following documents are essential to the application of this Document. For the dated documents, only the versions with the dates indicated are applicable to this Document; for the undated documents, only the latest version (including all the amendments) is applicable to this Document.

GB/T 3249 Test method for fisher number of metal powders and related compounds

GB/T 4324 (all parts) Methods for chemical analysis of tungsten

GB/T 5124.1 Methods for chemical analysis of hard-metals - Determination of total carbon content - Gravimetric method

GB/T 5124.2 Methods for chemical analysis of hard-metals - Determination of insoluble (free) carbon content - Gravimetric method

GB/T 5314 Powders for powder metallurgical purposes - Sampling

GB/T 13390 Metallic powder - Determination of the specific surface area - Method of nitrogen adsorption

YS/T 559 Methods for emission spectrum analysis of tungsten

3 Requirements

4 Test Method

4.1 The main composition content is calculated by impurity reduction method.

4.2 The determination of impurity content shall be carried out according to the provisions of GB/T 4324 or YS/T 559; and the arbitration analysis method shall be carried out according to the provisions of GB/T 4324.

4.3 The determination of the average particle size shall be carried out in accordance with the provisions of GB/T 3249.

4.4 The determination of the specific surface area shall be carried out in accordance with the provisions of GB/T 13390.

4.5 The determination of the total carbon content shall be carried out according to the provisions of GB/T 5124.1; the determination of the free carbon content shall be carried out according to the provisions of GB/T 5124.2; and the combined carbon content shall be obtained by subtracting the free carbon content from the total carbon content. The determination of total carbon and free carbon contents can also be carried out according to the method negotiated between the supplier and the purchaser.

4.6 The determination of oxygen content shall be carried out according to the provisions of GB/T 4324.

4.7 Sieving shall be carried out in a manner agreed upon by both the supplier and the purchaser.

4.8 The appearance quality shall be inspected visually.

5 Inspection Rules

6 Marking, Packaging, Transportation, Storage and Quality Certificate

7 Order Form (or Contract) Content

The order form (or contract) shall include the following contents:

a) Product name;

b) Product designation; […]