A process for the preparation of a thin casting made of stainless cr - steel.

摘要

PURPOSE:To eliminate a stage corresponding to annealing of a hot rolled sheet and to obtain a thin sheet having good cold rollability and ridging characteristic in the stage of producing a thin-walled slab of a titled steel having a specific compsn. by subjecting the slab after casting to cooling and precipitation treatment under prescribed conditions. CONSTITUTION:A Cr stainless steel essentially consisting, by weight, of 8-30% Cr, 0.001-0.5% C, 0.001-0.5% N and 0.001-0.5% Al and consisting of the balance Fe is cast to the slab having a prescribed thickness or below. Such slab is cooled at a rate above air cooling from the solidification temp. down to the gamma phase precipitation temp. to prevent the precipitation of the gamma phase as far as possible. The slab is subjected to rolling during or after said cooling if necessary. The above-mentioned slab is then subjected to the precipitation treatment for =10sec at 700-1,000 deg.C to precipitate the C, N, S, etc. solutionized in supersaturation in the alpha phase in the form of carbonitride and sulfide by the above-mentioned quick cooling by which the cold rollability and the elongation of the final product are improved and the yield point is lowered. The slab is otherwise heated up to the alpha+gamma two-phase region to precipitate the gammaphase after the above-mentioned cooling.