变形量及碳含量对超低碳贝氏体钢动态再结晶的影响

Effect of Deformation and Carbon Content on Dynamic Recrystallization of Ultra-Low Carbon Bainite Steel

采用Thermechmastor-Z热模拟试验机对0.019%C和0.052%C的两种超低碳贝氏体(ULCB)钢进行单道次热压缩试验,变形温度为1100℃,应变速率为2s^(-1),变形量为5%～50%。结果表明,当变形量低于40%时。两种ULCB钢的形变再结晶规律相同:经10%变形后产生再结晶晶核,20%变形后发生部分再结晶,变形40%后基本完成再结晶。当变形量超过40%后,0.052%C ULCB钢中晶粒比0.019%C ULCB钢细小均匀。

The single pass thermal compression test of 0. 019C and 0. 052C two kinds of ultra-low carbon bainite （ULCB） steel with deformation 5% -50%, strain rate 2 s^-1 at 1 100 ℃ has been carried out by Thermeehmastor-Z thermal simulation machine. Results showed that as deformation was lower than 40% the deformation-recrystaUization behavior of two kinds of ULCB steel was same that was to form crystal nucleus of recrystallization with I0% deformation, partially recrystallize with 20% deformation, and basically perform recrystallization with 40% deformation. With deformation morethan 40%, the grain size of 0. 052C ULCB steel was more fine and uniform than that of 0. 019C ULCB steel.