ASTM A0904-26
Standard Specification for 50 Nickel-50 Iron Powder Metallurgy Soft Magnetic Parts
| Standard number: | ASTM A0904-26 |
| Released: | 01.01.2026 |
| Status: | Active |
| Pages: | 3 |
| Section: | 03.07 |
| Keywords: | 50 Ni-50 Fe; coercive field strength; powder metallurgy; |
| ASTM number: | ASTM A904 |
| Supersedes: | A0904-20 |
This specification covers the magnetic property requirements of 50 nickel-50 iron soft magnetic parts fabricated by powder metallurgy techniques in the sintered or annealed conditions, intended for parts that require high magnetic permeability, high electrical resistivity, low coercive field strength, and low hysteresis loss. This specification does not cover parts produced by metal injection molding. Parts shall be tested and adhere to the chemical composition, sintered density and coercive field strength requirements listed in this specification. Appendices contain information on typical magnetic properties and heat treatment.
1.1 This 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.
1.2 This 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.
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to customary (cgs-emu and inch-pound) units, which are provided for information only and are not considered standard.
1.3.1 There are selected values presented in two units, both of which are in acceptable SI units. These are differentiated by the word “or,” as in “μΩ-cm, or, Ω-m.”
1.4 This 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.