PURPOSE: To prevent the generation of cracks in a stainless steel in the case of high speed continuous press working by incorporating specified amounts of C, Si, Mn, Ni, Cr, Cu, N Mo and Fe therein.
CONSTITUTION: The compsn. of this stainless steel is constituted of the one contg., by weight, ≤0.05% C, 1 to 2.5% Si, ≤5% Mn, 5 to 9% Ni, 14 to 19% Cr, ≤4% Cu, 0.04% Ni and ≤1% Mo, and the balance substantial Fe. Moreover, (C+N); <0.06 and (a) value; -0.3 to 1 are satisfied; where (a) value = 19.43-10.8 C-0.14Si-0.54Mn-1.02Ni-0.57Cr-0.49Cu-7.53N. As for the relationship between the ratio of the amt. of a martensitic phase to the amt. of an austenitic phase and the amt. of work strain, the (a) value is introduced from the experimental result. In the case the (a) value is small, the austenitic phase can be valued as being stable. Multistage press working can be executed by high speed continuous pressing.
MIYAKUSU KATSUHISA
OKUBO NAOTO
