PRODUCTION OF CR-NI-BASED STAINLESS STEEL THIN SHEET EXCELLENT IN SURFACE QUALITY AND MATERIAL QUALITY

摘要

PURPOSE:To produce a Cr-Ni-based stainless steel thin sheet excellent in surface quality and material quality by casting Cr-Ni-based stainless steel having the specified compositional relation into a thin cast piece in N2 and holding it at the specified temp. and thereafter performing cold rolling and final annealing. CONSTITUTION:A thin cast piece having =6mm sheet thickness is cast from Cr-Ni-based stainless sheet such as 18%Cr-8%Ni. The product of a cold-rolled thin sheet is obtained by omitting hot rolling. In the above-mentioned production, the component delta-Fecal (however delta-Fecal=3(Cr+1.5Si+Mo+Nb+Ti)-2.8(Ni+0.5 Mn+0.5Cu)--84(C+N)-19.8%) of Cr-Ni-based stainless steel is controlled to 0-10%. Molten steel of this component is cast in the atmosphere contg. N2 or He as a main component. Then after the obtained thin cast piece is held at the temp. region of 800-1250 deg.C for =80min, it is annealed in accordance with necessity and cold-rolled and final annealing is performed. Thereby an austenite-based stainless steel thin sheet excellent in surface quality and material quality is economically obtained in a simple process.