【作者】 渠秀娟； 李维娟； 巨东英；

【Author】 QU Xiu-Juan~(1,2) LI Wei-Juan~1 JU Dong-Ying~1 (1.School of Materials Science and Engineering,Liaoning University of Science and Technology,Anshan 114051,China; 2.Medium Heavy Plate Plant of Angang Steel Co.,Ltd.Anshan 114042,china)

【机构】 辽宁科技大学材料科学与工程学院；

【摘要】 采用 Gleeble-1500热模拟试验机测量了 Cr-Mo 钢在1～90℃/s 的冷却速度下奥氏体连续冷却过程中的温度-膨胀曲线, 用 origin 软件进行数据处理,获得了实验钢的 CCT 曲线；同时测量了施加轴向载荷为0、40MPa、80MPa 和120MPa 的压应力时奥氏体连续冷却过程中的温度-膨胀曲线,冷却速度分别为50℃/s、70℃/s 和90℃/s。利用杠杆定律,根据不同温度下的膨胀量计算得到贝氏体相变动力学曲线,研究了压应力对贝氏体相变动力学和贝氏体相变温度的影响。结果表明,在以冷却速度为50℃/s 和70℃/s 连续冷却时,压应力抑制前期阶段的贝氏体相变,促进后期阶段的贝氏体相变；在以冷却速度为90℃/s 连续冷却时,压应力对整个贝氏体相变过程都有促进作用,特别是应力较大时；压应力使贝氏体相变开始温度 B_s 升高,贝氏体相变终了温度 B_f 降低。更多还原

【Abstract】 The temperature-expansion diagrams of anstenite continuous cooling were measured for a Cr-Mo steel at cooling rates of 1～90℃/s with Gleeble-1500 thermal simulator.Then the CCT diagram of experiment steel was obtained by data handled with origin software.The temperature-expansion diagrams of austenite continuous cooling were also measured at cooling rate of 50℃/s,70℃/s and 90℃/s under axial pressure stress of 0,40MPa,80MPa and 120MPa.Through expansion volume of different temperature the diagrams of bainitic transformation kinetics were gained.Effect of pressure stress on bainitic transformation kinetics and phase temperature were studied.The results show that pressure stress restrains bainitic transformation on earlier stage and accelerates it on later stage at 50℃/s and 70℃/s continuous cooling rates;On the other hand ,pressure stress accelerates bainitic transformation at 90℃/s continuous cooling rates,especially larger pressure stress;pressure stress causes B_s higher and B_f lower.更多还原