GB/T 3458-2006Tungsten Powder (English PDF)

Foreword

This Standard is a revision to GB/T 3458-1982 "Technical Requirements of Tungsten Powders".

Compared with GB/T 3458-1982, the major changes in this Standard are as follows.

- Tungsten powder is divided into 14 specifications according to the granularity;

- For FW-1, impurity element indexes such as Pb, Bi, Sn, As, Sb or Mn are added; for FW-1 and FWP-1, impurity element index Cu is added; content of some impurity elements of 3 designations was reduced; for FW-1 and FW-2, the oxygen content index is adjusted according to the granularity;

- Requirements for mesh number of FW-1 and FW-2 are deleted;

- Sieve-screening and apparent density of FWP-1 are adjusted.

1 Scope

This Standard specifies tungsten powder's requirements, test methods, inspection rules, marking, packaging, transportation, storage, and contract contents.

This Standard is applicable to tungsten powder that is made by hydrogen reducing tungsten oxide.

2 Normative References

The following standards contain provisions which, through reference in this Standard, constitute provisions of this Standard. For dated references, the subsequent amendments (excluding corrigendum) or revisions of these publications do not apply.

However, parties who enter into agreement according to this Standard are encouraged to investigate whether the latest editions are applicable. For undated references, the latest edition of the standard referred to applies.

GB/T 1480 Determination of Particle Size for Metallic Powders - Dry Sieving

GB/T 2596 Tungsten Powder and Tungsten Carbide Powder - Determination of Specific Surface Product (Average Graininess) - Simplified Nitrogen Absorption Method

3 Requirements

3.4 Physical properties such as apparent density and particle-size distribution of FW-1 and FW-2 may be negotiated by supplier and purchaser.

3.5 For FWP-1, the powder weight with particle-size between 0.075 mm (-200 mesh)

~ 0.045 mm (+325 mesh) is not less than 80%, and apparent density is (4.0~8.0) g/cm³.

4 Test Methods

4.1 Chemical composition analysis of tungsten powder is carried out according to GB/T 4324.

4.2 Fisher average particle-size determination of tungsten powder is carried out according to GB/T 3249.

4.6 Visual inspection is carried out for the appearance quality of tungsten powder.

5 Inspection Rules

6 Marking, Packaging, Transportation, and Storage

6.1 Products are packaged with metal bucket, and sealed with polyethylene plastic bag. The weight of each piece may be negotiated by supplier and purchaser.

6.2 External package of the products shall be noted with. supplier name, product name and designation, specification, batch No., net weight, and accompanied with words or marks such as "damp proof" or "upward".

6.3 Each batch of products shall be accompanied with quality certificate, and noted with.

6.4 During transportation, the products shall be free from humidity and strenuous collision.

7 Contract (or Order) Contents

Contract (or order) shall include the following contents. […]