Kabushiki Kaisha Toshiba

Tastuyoshi Aisaka

Takanobu Nishimura

Motoo Suzuki

A cast iron having an austenitic matrix and consisting essentially of from 1% up to 3.5% carbon, up to 1.5% silicon, from 32% to 39.5% nickel, from 1% to less than 4% cobalt, up to 41% of the combined total of nickel plus cobalt and the balance substantially all iron provides a low expansion coefficient, good castability, good cutting properties and good damping capacity. (% is meant for % by weight)

Low expansion cast iron

A lapping tool with a flatness in the range below 20 .mu.m which is made of at least cast iron having an austenitic matrix and consisting essentially of from 1% up to 3.5% carbon, up to 1.5% silicon, from 32% to 39.5% nickel, from 1% to less than 4% cobalt, up to 41% of the combined total of nickel plus cobalt and the balance substantially all iron providing a low expansion coefficient, good castability, good cutting properties and good damping capacity. (By % is meant % by weight).

Growing community of inventors

Kanagawa, Japan

Tastuyoshi Aisaka