Kotaro Honda (本多 光太郎, Honda Kōtarō), born on February 23, 1870, in Okazaki, Aichi Prefecture – February 12, 1954) was a Japanese metallurgist and inventor. He invented KS steel (initials from Kichiei Sumitomo), which is a type of magnetic resistant steel that is three times more resistant than tungsten steel.[1] This material, which had 250 oersteds magnetic resistance, was developed through rigorous basic research on steel and alloys.[2]
Honda's research on KS steel in 1917, and on improved KS steel in 1934 became the basis for his position that Japan's industrial development is dependent on basic research in major scientific fields.[3] He later improved upon the steel, creating NKS steel. NKS steel was mentioned by Taiichi Ohno in his book as being one of the Japanese materials whose development was tied to World War II.[4]
Honda, together with the academic Tokiatsu Hojo, setup up a research institute, which was supported by the Sumitomo family.[2] It was later renamed Metallic Materials Research Institute.[2] In 1931, he was appointed president of Tohoku Imperial University, where he taught physics for several years.[5]