TiC颗粒增强钛基复合材料的热变形行为及加工图

Hot deformation and processing map of titanium matrix composites reinforced by TiC particulates

在Gleeble-1500热模拟实验机上对原位生成TiC颗粒增强钛基复合材料进行热压缩实验,研究变形温度为700-950℃,应变速率为0.001-1 s-1时的热变形行为。研究结果表明：变形温度和应变速率对流变应力有显著影响,流变应力随变形温度的升高而降低,随应变速率的增加而升高。原位生成钛基复合材料在（α＋β）相区激活能为357.09 kJ/mol,β相区激活能为227.18 kJ/mol,采用Zener-Hollomon参数法构建其高温塑性变形的本构关系。根据动态材料模型,建立原位生成钛基复合材料的加工图,并确定热变形的流变失稳区域。

The deformation behaviour of in-situ synthesized titanium matrix composites reinforced by TiC particulates was investigated by compression tests on Gleeble-1500 thermal simulator machine.The tests were performed in the temperature range from 700 to 950 ℃ and strain rate range from 0.001 to 1 s-1.The results show that the flow stress is controlled by strain rate and deformation temperature.The flow stress increases with the increase of strain rate and decreases with the increase of deformation temperature.The deformation activation energy is 357.09 kJ/mol in（α＋β） phase region and 227.18 kJ/mol in β phase region.The constitutive equation of the plastic deformation is obtained by introducing Zener-Hollomon parameter.The processing maps of in-situ synthesized titanium matrix composites are also established based on the dynamic material model and the flow instability region is noted.