通过采用双道次热压缩的实验方法,在Gleeble-1500D热模拟机上对铸态30Cr2Ni4MoV钢在高温变形时的静态再结晶软化行为进行研究。根据实验结果,分析变形温度、初始晶粒尺寸以及道次间隔时间等不同工艺参数对铸态30Cr2Ni4MoV钢静态软化行为的影响;构建该铸态材料的静态再结晶动力学模型及晶粒尺寸模型,获得该铸态材料的再结晶激活能为207.39 k J·mol-1。通过实验结果可知：该铸态材料的静态再结晶体积分数随温度的升高、应变的增加、应变速率的加快和道次间隔时间的不断延长而增加,却几乎不受初始晶粒尺寸的影响。对比分析热压缩所得到的实验值与该模型的计算值,验证了所建模型的准确性。
In order to determine the critical forging penetration efficiency （FPE） of 06Crl9NigNbN steel, a new model was presented to describe critical FPE, which is significant to optimize the steel forging process. The plane strain compression tests were conducted to obtain the model and confirm its va- lidity. The results indicated that the dynamic recrystallization （DRX） volume fraction increases and the grain size decreases with the rise of reduction ratio. Meanwhile, the compression process was simulated by DEFORM software. The tensile tests were conducted and the results demonstrated that the mechanical properties gradually become stable when the reduction ratio increases to 30%, 34% and 40% at 1200, 1 100 and 1000 ℃, respectively. The calculated results based on this new model are consistent with experimental results, indicating that the model is suitable to predict the critical FPE for the steel.
Yong-xing JiaoJian-sheng LiuXing-wang DuanXiao-hua ZhengWen-wu He
