CPC C21D 7/13 (2013.01) [C21D 6/004 (2013.01); C21D 6/005 (2013.01); C21D 6/007 (2013.01); C21D 6/008 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/44 (2013.01); C22C 38/50 (2013.01); C22C 38/52 (2013.01); C21D 2211/001 (2013.01); C21D 2211/008 (2013.01)] | 20 Claims |
1. A method for heat treatment of a stainless steel comprising:
13 to 14 wt % chromium (Cr);
5.5 to 7.0 wt % nickel (Ni);
5.5 to 7.5 wt % cobalt (Co);
3 to 5 wt % molybdenum (Mo);
1.9 to 2.5 wt % titanium (Ti); and
iron (Fe),
the method comprising:
solution treatment of the stainless steel at 1050-1150° C. for 1-2 h;
after the solution treatment, cryogenic treatment of the stainless steel in liquid nitrogen (−196° C.) for at least 5 h; and
after the cryogenic treatment, aging treatment of the stainless steel at 450-520° C. for 30 min to 16 h.
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