基于原位观测的Cr5合金钢Hansel-Spittel高温本构模型修正方法及试验验证

Correction method and experimental verification of Hansel-Spittel constitutive model of Cr5 alloy steel at high temperature based on in-situ observation

为了得到能够准确描述Cr5合金钢的变形行为的高温本构模型,采用Gleeble-1500D热模拟试验机进行了Cr5合金钢试样的高温拉伸试验,对Cr5合金钢的整个拉伸断裂过程进行了原位观测,获得了Cr5合金钢在温度为800~1150℃,应变速率为0.01、0.1、1和5 s-1条件下的真应力-应变曲线。采用高速摄像设备对Cr5合金钢试样的高温拉伸试验过程进行了拍摄和记录,通过拉伸试验的原位观测得到了Cr5合金钢拉伸试样缩颈时的直径d和试样缩颈处的曲率半径R。采用齐别尔(Siebel)公式对Cr5合金钢的拉伸试验数据进行了修正,建立了修正后的Cr5合金钢Hansel-Spittel高温本构模型。结果表明,修正后的Cr5合金钢Hansel-Spittel高温本构模型拟合出的相关系数值为0.97,模型计算值和试验值之间的误差较小,验证了该模型的准确性。

To obtain the high temperature constitutive model that can describe the deformation behavior of Cr5 alloy steel accurately,the high temperature tensile test of Cr5 alloy steel samples was carried out on Gleeble-1500 D thermal simulation testing machine,and the in-situ observation of whole tensile fracture process of Cr5 alloy steel was conducted. The true stress-strain curves of Cr5 alloy steel under the condition of temperature of 800-1150 ℃ and strain rate of 0. 01,0. 1,1 and 5 s-1 were obtained. The high temperature tensile test process of Cr5 alloy steel samples was photographed and recorded by high-speed camera equipment. The diameter d and the curvature radius R at the necking position of Cr5 alloy steel tensile samples were obtained by in-situ observation of the tensile test. The tensile test data of Cr5 alloy steel was modified by Siebel formula,and the modified Hansel-Spittel high temperature constitutive model of Cr5 alloy steel was established. The results show that the correlation coefficient of the modified Hansel-Spittel high temperature constitutive model of Cr5 alloy steel is 0. 97,and the error between the calculated value of model and the test value is small,which verifies the accuracy of the model.