Abstract: The single pass compression test of <I)30 mm intermediate billet of cold heading steel SWRCH22A (/% : 0. 18 ~0. 20C, ≤0. 050Si, 0. 80 ~0. 88Mn, ≤0. 020P, ≤0. 015S, ≥O. 025Al) with strain rate 0. 1 ~20 s^-1, real strain ≤1.0 at 850 ~ 1 000℃ has been carried out by using Gleeble-1500D thermal simulator to get true stress-stress curves of the steel with different deformation parameters. Test results show that with increasing temperature and decreasing strain rate, the flow stress of steel decreases, and its dynamic crystallization occurs easily with low strain rate at higher temperature. The dynamic recrystallization deforming energy of steel SWRCH22A Q_def = 328 264 J/mol. The flow stress model and dynamic crystallization equation of cold heading steel SWRCH22A are obtained by regression analysis. The model calculation value nicely coincides with the test measured value.

摘要： 采用Gleeble-1500D热模拟试验机,对Φ30 mm SWRCH22A冷镦钢中间坯(/%:0.18～0.20C、≤0.05Si、0.80～0.88Mn、≤0.020P、≤0.015S、≥0.025A1)进行850～1000℃、变形速度O.1～20 s^-1、真应变≤1.0的单道次压缩变形试验,得出该钢在不同变形条件下的真应力应变曲线:试验结果表明,随着温度的升高及应变速率的降低,钢的流动应力降低,且动态再结晶在高变形温度和低变形速率下更容易发生。SWRCH22A钢的动态再结晶变形能Q_def=328 264 J/ml。通过回归分析得到了SWRCH22A冷镦钢的流动应力模型和动态再结晶动力学方程,模型计算与试验结果吻合。

关键词: SWRCH22A冷镦钢, 单道次热压缩, 模拟试验, 流动应力, 动态再结晶