PRODUCTION OF BIMETAL

摘要

PURPOSE:To produce bimetal without degradation in a curving constant and mechanical properties by rolling an alloy on a high expansion side and an alloy on a low expansion side at the specific temp. higher than the martensite transformation temp. of the alloy on the high expansion side. CONSTITUTION:The temp. for rolling is set at the martensite transformation temp. of an alloy on a high expansion side that causes martensite transformation by cold rolling +30 deg.C, more preferably +60 deg.C, whereby the martensite transformation is prevented and the degradation in the curving constant occuring in the decrease in the coefft. of thermal expansion is prevented in the stage of producing bimetal by rolling said alloy on the high expansion side and an alloy on a low expansion side with or without intervention of an alloy of an intermediate layer. The rolling temp. is kept at <=500 deg.C to prevent the degradation in mechanical properties. Alloy steel contg. about 15-30wt% Ni and about 1-15% Cr is used as the above-mentioned alloy on the high expansion side and an invar alloy or the like is used for the alloy on the low expansion side.