(1. 中南大学 材料科学与工程学院，长沙 410083；
2. 广州有色金属研究院，广州 510650)
摘 要: 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 ℃、温度间隔为50 ℃，应变速率为10−3~1 s−1条件下的热变形行为，采用XRD、DSC、SEM、OM等实验手段对复合材料的相变点及变形后的显微组织等进行分析和测定。结果表明：流变应力随变形温度的升高和应变速率的降低而减小；在高应变速率条件下，绝热温升对流变应力的影响较为明显；动态再结晶是TiC钛基复合材料热变形的重要机制，变形温度越高，再结晶越易进行，变形速率越高，应变量越大，再结晶晶粒越细小。
关键字: 钛基复合材料；高温变形；流变应力；显微组织
titanium based matrix composites reinforced by TiC particulates
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Guangzhou Research Institute of Non-ferrous Metals, Guangzhou 510600, China）
Abstract:The deformation behavior of in-situ synthesized titanium matrix composites reinforced by TiC particulates were investigated by compression tests on Gleeble−1500 thermal simulator machine. The microstructures of titanium matrix composites and phase transition temperature were investigated by means of XRD, DSC, OM, SEM. The tests were performed in the temperature range from 700 ℃ to 950 ℃ with interval of 50 ℃, and strain rates range of 10−3−1 s−1. The results show that the flow stress decreases with increasing deformation temperature and decreasing strain rate. When the strain rate is high, the influence of adiabatic temperature to the flow stress is considerable. The dynamic recrystallization is an important deformation mechanism for in-situ synthesized titanium matrix composites reinforced by TiC particulates. The dynamic recrystallization happens more easily with increasing temperatures. Smaller recrystallization grains can be got with higher strain rate and strain.
Key words: titanium based matrix composites; high temperature deformation; flow stress; microstructure
