Technical Info

Technical Advantages Of CMI Electromagnetic Products

Until 1975, ARMCO STEEL CO. produced two grades of Magnetic Iron, Ingot Iron and EMI (a low aging version of Ingot Iron). Neither of these products are available today.

Substitute materials, such as C1005, C1010, and Low Carbon Steel are marginally adequate for electromagnetic applications after expensive heat treatment but, at best, do not meet the stringent requirements of today’s modern relays, solenoids and other electromagnetic devices,.

Recognizing this problem, CMI Specialty Products, Inc. developed the CMI product line – using a proprietary metal chemistry and processing procedure. CMI products exhibit such superior magnetic properties that other materials, including the old Ingot Iron, became obsolete for today’s hi-tech electromagnetic devices. From its beginning, CMI was active in magnetics research. We were instrumental in upgrading the Electromagnetic Iron specification ASTM A-848, setting forth more stringent requirements for COERCIVITY (Hc), the fundamental parameter governing the Hysteresis performance of the material. CMI products are represented and sold to this specification as well as many other specifications. (see data sheets)

CMI specializes in ultra low carbon electromagnetic iron, not merely low carbon steel. CMI products are purchased from several mills in 240 ton heats to our specifications which provides the basis of our flexible proprietary processing, resulting in the desires magnetic properties of both annealed and unannealed applications. Custom processing for each order, as well as incoming, in-process and final magnetic properties inspection assure our customers of consistent properties, dimensions and the excellent quality that CMI is known for.

CMI quality results in such user benefits as reduced adjustment rate for relays; less copper turns in relays and solenoids, reducing heat buildup, weight, magnetic circuit metal weight; higher BAUD rate for computer tape heads and flux collectors; higher saturation and tip induction in air gap applications such as high performance loudspeaker device and magnetic bearings – and any other DC electromagnetic device requiring the highest quality and reliability.