June 8, 2001 - A new soft magnetic alloy with reduced cobalt content offers high saturation magnetization (flux density) and relatively high electrical resistivity for applications in the automotive industry and other industries requiring lower material cost.

Hiperco® Alloy 15, an addition to Carpenter Technology's well-known Hiperco family of soft magnetic alloys, can be considered for many new and high performance applications where cost considerations have restricted the use of higher-cobalt soft magnetic materials.

This 15Co-2.7Mn-Fe alloy is a candidate for applications such as high performance electromagnets, dot-matrix printers, linear motors, actuators, relays, fuel injectors, switched reluctance motors, magnetic bearings, flywheels and sensors. It also could be used for solenoids, particularly those which have to be turned on
and off with greater force.

Hiperco Alloy 15 has a high magnetic saturation of 22.3-22.8 kilogauss, and demonstrates substantially higher flux density than that of iron and silicon-irons at high fields. It possesses high electrical resistivity for AC applications of 38-42 micro-ohm-centimeters, compared with Hiperco Alloy 27, which is 19 micro-ohm-centimeters. The new grade's coercivity is relatively low at 1.9 to 2.4 oersteds.

With its unique combination of low cost and high magnetic induction values, the new alloy may be considered as a lower cost solution for some applications where the magnetic performance of Hiperco Alloy 50 or Hiperco Alloy 27 were desired, but usage was prohibited by their high costs.

Hiperco Alloy 15 also may serve as a substitute for materials such as nickel-irons, ferritic stainless steels, silicon irons and iron that do not provide adequate flux density for their intended applications.

Unlike the higher-cobalt alloys, Hiperco Alloy 15 is ductile at room temperature. It can be forged to produce bulk pieces, or cold-compacted in powder forms. It also can be made into strip products. While it can be processed by stamping and machining, it also can be easily bent and formed. Carpenter suggests that this good ductility could permit parts production by newer manufacturing technologies.

The composition of Hiperco Alloy 15 has been balanced to achieve the most favorable combination of high resistivity and good soft magnetic performance. Its magnetic properties can be optimized by a two-step annealing process - heating first at 2156°F (1180°C), then holding at 1292°F (700°C).

Hiperco Alloy 15 is available in strip, bar and plate forms. Carpenter has offered to work with designers and materials specifiers on specific applications.