GB/T 26726-2019Ultrafine tungsten powder (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard replaces GB/T 26726-2011 "ultra-fine tungsten powder", compared with GB/T 26726-2011, except for editorial modification The changes are as follows.

--- Subdivide the product grade and increase the FWN15, FWN20, FWN40, FWN50, FWN70 five grades of ultra-fine tungsten powder and Related requirements, deleted the FWN60 grade, adjusted the requirements of the FWN30 grade, and added Table 3 (see Chapter 3, 2011) Chapter 3 of the edition);

--- The content of W is changed from "balance" to not less than "99.95%" (see Table 1, Table 1 of the 2011 edition);

--- Increase the content requirements of Cd, Co, Cr, S, Ti, V (see Table 1, Table 1 of the 2011 edition);

--- Refining the carbon content requirements according to the product grade (see Table 1, Table 1 of the 2011 edition);

--- Increase "arbitration analysis in accordance with the provisions of GB/T 4324" (see 4.1, 2011 version 4.1);

--- The average particle size of the product is calculated according to the specific surface area, increasing the formula (1) (see 4.3, 2011 edition 4.2).

1 Scope

This standard specifies the requirements, test methods, inspection rules and signs, packaging, transportation, storage, quality certificates and contracts for ultra-fine tungsten powder. (or order form) content.

This standard applies to ultra-fine tungsten powder prepared by hydrogen reduction of tungsten oxide.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 4324 (all parts) Tungsten chemical analysis method

GB/T 5314 powder metallurgy powder sampling method

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

YS/T 559 tungsten emission spectrum analysis method

3 Requirements