ASTM A 904 : 2014 : REDLINE

1.1This specification covers the magnetic properties of 50 nickel-50 iron parts fabricated by powder metallurgy techniques and is intended for parts that require high magnetic permeability, high electrical resistivity, low coercive field strength, and low hysteresis loss. It differs from the wrought alloy specification (see Specification A753) because these parts are porous. A number of magnetic properties such as permeability are proportional to the sintered density.

1.2This specification deals with powder metallurgy 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.

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

1.4This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.