PURPOSE: To obtain a stainless steel usable for a thin sheet, a gasket or the like by executing componental regulation in a steel to form its phase into a metastable austenitic one in a solid soln. state and executing cold rolling or cold working to transform a part of the phase into a martensitic one.
CONSTITUTION: A stainless steel constituted of, by weight, ≤0.03% C, >3.0 to 5% Si, >1.0 to 5% Mn, 13 to 17% Cr, 5 to 9% Ni, 0.05 to 0.20% N and the balance Fe is subjected to ≥10% cold rolling and is thereafter heated at 300 to 600°C for 0.1 to 30hr. In this way, the stainless steel in which the phase is constituted of a metastable austenitic one in a solid soln. state and a part of the phase is transformed into a martensitic one can be obtd. In this steel, C is effective for strengthening martensite, but in the case it is too much, its intergranular corrosion cracking sensitivity is increased. Si highly rises its strength, but in the case it is too much, its hot workability is deteriorated. Mn is required for securing the content of N, but in the case it is too much, the above transformation is deteriorated in the same manner as Ni. N is important for strengthening the above both phases, and the deterioration of its ductility by the strengthening is small, but in the case it is too much, blow holes are formed at the time of casting.
NAKAZAWA TAKANORI
TAKESHITA TETSUO
ARAKAWA MOTOHIKO
MINAMINO SHIGERU
| JPH02225647A | 1990-09-07 | |||
| JPS63317628A | 1988-12-26 | |||
| JPS61295356A | 1986-12-26 | |||
| JPS5721030A | 1982-02-03 |
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