Soft magnetic alloys are ferromagnetic materials that are easily magnetized and de-magnetized. To provide optimal magnetic performance, these alloys possess very low levels of carbon, nitrogen, and oxygen. They rely on various additions of phosphorus, nickel, and silicon to optimize magnetic induction, permeability, and coercive force. The magnetic properties of all of these alloys benefit from high temperature sintering (HT) above 2200 F (1200 C) in hydrogen, as compared to the standard PM sintering process (ST) in metal mesh belt furnaces at nominally 2050 F (1120 C). Density and grain size increases, while residual levels of carbon, oxygen, and nitrogen are reduced. Typical applications include tone wheels, relays, cores, sensor probes, armatures, solenoid components, and pole pieces.

The following tables contain a list of the materials available. For more complete coverage of properties, reference MPIF Standard 35, ASTM B783, ISO 5755, DIN 30910-4, and JIS Z2550, and download the technical information bulletins of interest. Standard powder metal materials are defined in North America by MPIF Standard 35 and ASTM B783, essentially equivalent standards. German PM steels are listed in DIN 30910-4, or more recently, ISO 5755. Japan steels are listed in JIS Z2550, with grade names changing with the revision from 1989 to 2000.

Density ranges for the materials listed are typically for single-pressed parts. Higher densities can be achieved with double-pressing. “HTS” indicates the material has been “high temperature sintered”, i.e. sintered at a minimum temperature of 2200 F (1200 C).