TiC含量为30%的TiC/Cu-Al_2O_3复合材料的热压缩行为

Hot Compressive Deformation Behavior of 30% TiC/Cu-Al_2O_3 Composite

利用Gleeble-1500D热力模拟试验机,在温度为450~850℃、应变速率为0.001~1.000s-1、真应变量为0.7的条件下,对TiC含量为30%的TiC/Cu-Al2O3复合材料进行了热压缩试验,研究了其流变应力及本构方程。结果表明,材料的流变应力-应变曲线主要以动态再结晶软化机制为特征,峰值应力随变形温度的降低或应变速率的升高而增加,属于温度和应变速率敏感材料;在真应力-应变曲线基础上,建立的TiC/Cu-Al2O3复合材料高温本构模型可较好地表征其高温流变特征。

Using the Gleeble-1500D simulator, the high-temperature plastic deformation behavior, the flow stress and constitutive equation of 30% TiC/Cu-Al_2O_3 composites were investigated at 450-850℃ with the strain rate of 0. 001 1 s-1 and total strain of 0.7. The results show that the high-temperature flow stress-strain curves of the composites are characterized by softening mechanism of the dynamic re- crystallization, and the peak stress is increased with the decrease of deformation temperature or the in- crease of strain rate, which reveals that the composites belong to temperature and strain rate sensitive material. Based on the true stress-strain curves, the established constitutive equation represents the high-temperature flow behavior of 30% TiC/Cu-Al203 composites, and the calculated results of the flow stress are well agreement with the experimental ones.