ISO 4496:1978

Metallic powders — Determination of acid insoluble content in iron, copper, tin and bronze powders

The insoluble matter is generally considered to be acid-insoluble silica and silicates, carbides, alumina, and clays. The methods are applicable to lubricant-free powders. ISO 4496 specifies apparatus and reagents, sampling, procedure, expression of results and test report.