00Cr11Ni11MoTi超高强不锈钢粗大晶粒遗传特性

Hereditary Feature of Coarse Grain of Ultra-High Strength Stainless Steel 00Cr11Ni11MoTi

研究了00Cr11Ni11MoTi钢1150℃轧后原始粗大晶粒在780～900℃固溶处理的遗传特征。结果表明,该钢存在一个奥氏体重新形核、不再遗传粗大晶粒的临界温度(Ac),00Cr11Ni11MoTi钢Ac在870～900℃,远高于A_f相变点,在A_f～Ac加热均发生原始粗大晶粒遗传。As(630℃)～A_f(730℃)两相区预处理可使奥氏体重新形核的临界温度(Ac)降低,但在Ac温度以上这种预处理没有明显的晶粒细化作用。

Hereditary feature of original coarse grain of steel 00CrllNillMoTi roiled at 1 150 % and solid-solution treated at 780 - 900℃ has been studied. Results show that there is a critical temperature Ac for the steel, at which the austenite renews nucleation and the heredity of coarse grain do not carried out; the Ac of steel 00Cr11Ni11MoTi is 870 - 900 ℃ and higher than transformation point Af, and with heating at Af - Ac, the heredity of original coarse grain occurs. With pre-heat-treating in two-phase region As （630 ℃ ） - Af（730 ℃ ） , the critical temperature Ac to renew nucleation of austenite decreases, but it is not available to refine grain with pre-heat-treating at temperature higher than Ac.