PRODUCTION OF STEEL MATERIAL

摘要

PURPOSE:To obtain a steel material having extremely fine and uniform carbide structure with less variance in components and structure with high productivity by hot rolling a carbon steel or alloy steel contg. C in a specified amt. then subjecting the steel to patenting followed by low temp. annealing. CONSTITUTION:A carbon steel or alloy steel contg. >=0.4wt% and more preferably <=1.3wt% C is hot rolled at a temp. of preferably the Ar3 transformation point or above and under such condition under which the rolling end temp. attains particularly 750-850 deg.C. The carbon steel or alloy steel after the hot rolling is once cooled and is reheated or the steel is subjected to patenting at a constant holding temp. of preferably 400-650 deg.C at a prescribed plate thickness, width or wire diameter in succession to the above-mentioned hot rolling. The carbon steel or the like is thereafter subjected to low temp. annealing at a temp. of preferably the heating austenite transformation point (Ac1 transformation point) or below and the intended steel material having the fine and uniform structure of carbide is obtd.