Powder metallurgy — Vocabulary
1Key Takeaways
This document defines terms relating to powder metallurgy. Powder metallurgy is the branch of metallurgy which relates to the manufacture of metallic powders, or of articles made from such powders with or without the addition of non-metallic powders, by the application of forming and sintering processes.
2Expert Interpretation
An in-depth interpretation of the ISO 3252:2019 powder metallurgy international standard terminology system, systematic analysis of core concepts such as metal powder characteristics, forming process, sintering technology, etc., including 142 professional terminology definitions in 5 categories and technical key points analysis.
Standard Framework and Technological Evolution
| Version Comparison | ISO 3252:1999 | ISO 3252:2019 |
|---|---|---|
| Total Number of Terms | 126 items | 142 items |
| New Content | - | 16 Contemporary Common Terms |
| Normative References | None | New Chapter 2 |
Classification and analysis of core terms
3.1 Powder-related terms
Key definitions: Alloy powder(3.1.3) refers to metal powder that is partially or completely alloyed with at least two components. Its preparation process includes:
- Atomization(3.1.7): Dispersion of molten metal by high-speed gas/liquid flow
- Mechanical alloying(3.1.49): Solid-state alloying by high-energy ball milling
Technical indicators: Apparent density(3.1.6) The test needs to distinguish between free-flowing powder (ISO 3923-1) and non-free-flowing powder (ISO 3923-2) methods.
3.2 Forming process terms
| Forming method | Pressure type | Typical application |
|---|---|---|
| Cold isostatic pressing(3.2.10) | Liquid medium | Complex shape parts |
| Metal injection molding(3.2.55) | Shear force | Micro precision parts |
| Warm pressing(3.2.88) | Uniaxial pressing | High-density structural parts |
3.3 Sintering characteristic terms
Pore classification system:
- Type A pores(3.3.2): <10μm
- Type B pores(3.3.10): 10-25μm
- Type C pores(3.3.18): Clustered pores caused by carbon defects
Sintering process control: Oversintering(3.3.41) and Oversintering(3.3.42) The determination of class=instrument>under-sintering (3.3.72) requires a combination of temperature-time curve and final performance testing (ISO 4498 hardness test).
Implementation Recommendations
- Term Application: The cemented carbide industry should pay special attention to the accurate use of special terms such as binder phase(3.3.7) and skeleton(3.2.75)
- Testing Support: The powder flowability test (3.1.39) needs to be equipped with a flow meter(3.1.40) device in accordance with ISO 4490 requirements
- Process Optimization: The use of vibration-assisted filling(3.2.85) can improve the powder distribution uniformity of complex molds