LGB38MnV非调质钢热变形行为研究

Research on Hot Deformation Behavior of LGB38MnV Non-quenched and Tempered Steel

通过热模拟压缩试验,研究LGB38MnV非调质钢在不同温度及应变速率下的热变形行为。利用Gleeble3500热力学模拟机进行单道次高温压缩,分别得到变形温度为850℃、900℃、950℃、1000℃,应变速率为0.01 s^(-1)、0.1 s^(-1)、1 s^(-1)、10 s^(-1)时的应力-应变曲线,建立双曲正弦形式Arrhenius的本构方程。研究表明,当变形速率为0.01 s^(-1),变形温度为850℃~1000℃时进行热压缩,LGB38MnV钢会发生动态再结晶,当变形温度等于1000℃,且变形速率0.01 s^(-1)~1 s^(-1)时,LGB38MnV钢也会发生动态再结晶。LGB38MnV钢热变形的流变应力随着变形温度的升高而减小。

High temperature compression test of LGB38MnV non-quenched and tempered steel was carried out at different temperatures and strain rates,and the hot deformation behavior was studied.The isothermal compression test was conducted on Gleeble 3500 at the temperature 850℃、900℃、950℃、1000℃and strain rate of 0.01 s^(-1)、0.1 s^(-1)、1 s^(-1)、10 s^(-1),and the flow stress curves were obtained.A constitutive model that was expressed by the hyperbolic laws in an Arrhenius-type equation was established.It was abtained that dynamic recrystallization took place when rolled at deformation temperatures of 850 to 1000℃and strain rates of 0.01 s^(-1),it also took place when rolled at deformation temperatures of 1000℃and strain rates which are not greater than 1 s^(-1).The flow stress decreased with the increasing of the deformational temperature,and increased with the increasing of the strain rate.