Accession Number : AD0420236


Title :   MANGANESE-ALUMINUM FOR PERMANENT MAGNET MATERIAL,


Corporate Author : INDIANA GENERAL CORP VALPARAISO


Personal Author(s) : Bohlmann,M A


Report Date : May 1963


Pagination or Media Count : 26


Abstract : Manganese-aluminum alloys with 68-73% Mn were developed for permanent magnet material. Best magnetic properties were obtained in 71% Mn alloys. Maximum energy product was 4.0 x 10 to the 6th power GOe, reached by homogenization, controlled quenching, reducing area 86% by swaging in jackets, and annealing. Process parameters were studied to fine the optima for the brittle alloy. Deformation of the alloy produces a preferred magnetic axis and raises coercive force. Swaging was best, but deforming by turning cast bars into chips on a lathe gave the best ''particle'' magnets and was easiest. A review of the crystal and magnetic structures leads to the deduction that dislocation lines involve Mn atoms arranged antiferromagnetically which subdivide larger ferromagnetic regions. The magnetic saturation is not reached in practical magnetizing field. The magnetic induction decreases with increasing temperatures to Curie point. (Author)


Descriptors :   *MAGNETIC MATERIALS , ALLOYS , MELTING , CASTING , DEFORMATION , QUENCHING , MAGNETS , PROCESSING , MATERIAL FORMING , HARDNESS , METAL FORMING PRESSES


Distribution Statement : APPROVED FOR PUBLIC RELEASE