| 摘要 |
PURPOSE:To produce the title stainless steel sheet having excellent surface quality and material quality with the simple process by continuously casting a Cr-Ni stainless steel to a thin strip-like ingot under specific conditions, then subjecting the ingot to hot working to form the finer recrystal grains, coiling the ingot after cooling and subjecting the same to cold rolling. CONSTITUTION:The Cr-Ni stainless steel represented by 18% Cr-8% Ni steel is continu ously cast to the thin strip-like ingot having <=10mm thickness by a continuous casting machine in which the wall surfaces of the casting mold moves in synchronization with the ingot while the cooling rate at the time of solidifying is kept at >=100 deg.C/sec, by which the smaller gamma grains are formed. The ingot is then subjected to <=60% hot rolling in a >=900 deg.C temp. region to accelerate the recrystallization in the ingot and to form the finer gamma grains until <=50mu average gamma grain size is attained. The ingot is further cooled at >=50 deg.C/sec cooling rate in a 900 to 500 deg.C range and after the ingot is coiled in a <=650 deg.C temp. region, the ingot is made into a cold rolled sheet by the conventional method. The finer structure is formed in this way and the Cr-Ni stainless steel sheet having the excellent surface quality and the material quality is obtd. in this way. |
