ASTM A811-03(2008)

1.1 This specification covers parts produced from iron powder metallurgy materials.

1.2 This specification deals with P/M parts in the sintered or annealed condition. Should the sintered parts be subjected to any secondary operation that causes mechanical strain, such as machining or sizing, they should be resintered or annealed.

1.3 The values stated in customary (cgs-emu and inch-pound) units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units which are provided for information only and are not considered standard.

This specification covers soft magnetic iron parts fabricated by pressing and sintering of iron powder. The specification does not cover parts produced by metal injection molding. Parts produced to this specification shall have a minimum sintered density of 6.6 g/cm³ (6600 kg/m³) in the magnetically critical section of the part. Chemical requirements for the sintered part are given. Three grades distinguished by the measured maximum value of coercive field strength are defined. Apart from the required measurements of sintered density, chemical composition and coercive field strength, information on magnetic aging and its detection is given. Appendices containing magnetic and mechanical property data for a variety of sintering conditions are provided.