(中南大学 粉末冶金国家重点实验室，长沙 410083)
摘 要: TC18近β钛合金以其高强度、高断裂韧性和优良的抗腐蚀性能得到越来越广泛的应用，且有望通过改变加工方式和通过低温塑性变形改善其微观组织从而进一步提升合金的综合力学性能。通过准静态拉伸试验，实现TC18钛合金在低温下的塑性变形，通过对变形微观组织的观察分析，研究该合金在低温变形时的相变行为。结果表明；TC18钛合金能够在低温、低应变速率下发生塑性变形。低温下变形过程中主要发生ω相变，并且温度、应变会对ω相变行为产生一定的影响。
关键字: TC18钛合金；准静态拉伸；低温变形；低应变速率；ω相变
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:TC18 near β titanium alloy was wildly applied for its high strength, high breaking tenacity and good corrosion resistance. And it is possible to improve the comprehensive mechanical properties by changing the microstructure through low temperature deformation. The results show that the low temperature deformation of TC18 titanium alloy by using quasi static tensile test is elastic transformation, then, the phase transformation behavior of this alloy was investigated by observing and analyzing the microstructure. The plastic deformation of TC18 titanium alloy occurs under the low temperature and low strain rate. The ω phase transformation happens under low temperature, and will be affected by the temperature and strain.
Key words: TC18 titanium alloy; quasi static tensile; low temperature deformation; low strain rate; ω phase transformation
