C_(sf)/Mg复合材料热压缩流变行为及本构关系

Hot Compression Behaviors of C_(sf)/Mg Composite and Its Constitutive Relation

利用Gleeble1500D试验机对真空浸渗法制备的Csf/Mg复合材料进行热压缩试验,研究了在596~696 K,应变速率5×10-3~5×10-1s-1,最大真应变0.6变形条件下的塑性变形力学行为。根据Csf/Mg复合材料热压缩试验数据及其力学行为特征,采用多元非线性回归方法建立了其高温粘塑性力学本构关系模型,克服了以往Arrhenius模型只能计算峰值应力或稳态应力的不足。结果表明,流变应力的预测值与试验值绝对误差平均值为8.95%,相关系数0.9549。

Csf/Mg composite prepared by vacuum infiltration method was hot compressed on Gleeble1500 D simulator.The plastic deformation behavior was investigated at 596-696 K, strain rate of 5×10-3- 5×10-1s-1and the largest true strain of0.6. According to the experiment results, a strain compensated constitutive model was established by multivariate nonlinear regression method. The disadvantage of Arrhenius model only calculating the peak stress and steady state stress was overcomed. The results show the average error of the flow stress calculated by the established constitutive model and the experiment one is only 8.95%,and then the correlation coefficient is 0.9549.