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Tokushichi Mishima MK Magnetic Steel

(Prepared by Pubulic Relations Section Genneral Affairs Division)

Dr. Tokushichi Mishima of Tokyo Imperial University, who had been researching the special nature of nickel, invented strong magnet steel in 1931(MK magnetic steel) by adding aluminum to nickel.

Aside from patenting the invention in Japan, Dr. Mishima actively obtained patents for his invention overseas. Licenses for MK magnetic steel were obtained by Tokyo Steel Company of Japan, Bosch GmbH of Germany and General Electric of the United States, thereby contributing to development of industrial production on a global scale.

MK magnetic steel can be produced inexpensively and maintains a strong magnetic force even if miniaturized. Moreover, since the magnetism remains stable against thermal changes and vibrations, MK magnetic steel has contributed greatly to progress in such fields as electronics, communications devices, aviation, automobiles, measuring devices and control devices.

MK Magnetic Steel of various sizes used in a speaker

MK Magnetic Steel of various sizes used in a speaker

A KM Magnetic Steel memorial donated by Tokushichi Mishima to Hiroishi Elementary School

A KM Magnetic Steel memorial donated by Tokushichi Mishima to Hiroishi Elementary School in his hometown in 1950. There are two strips of MK Magnetic Steel above the stand, one of which floats above the other as a result of magnetic repulsion.

Linked from [Ten Japanese Great Inventors]

[Last updated 7 October 2002]