TC4/TC17线性摩擦焊接头组织及力学性能

Structure and mechanical properties of TC4/TC17 linear friction welding joint

针对航空发动机整体叶盘常用的TC4和TC17钛合金开展线性摩擦焊研究,对接头的组织进行了金相和电镜观察,并测量了焊接过程的温度.结果表明,接头分为母材、热力影响区和焊合区三部分,其热力影响区组织只发生了α相和β相沿受力方向的重新排列,焊合区发生了再结晶.温度测量表明,焊接过程的最高温度可达到1 270℃,超过了钛合金的β转变温度.拉伸测试表明,在室温和200℃进行拉伸测试时,接头的抗拉强度与TC4母材等强,而在400℃进行测试时,接头抗拉强度能达到TC4母材的95%.

TC4 and TC17 titanium usually used on aeroengine blisk were studied.The microstructures were analyzed by metallograph and transmission electron microscope.The temperature during the welding process was also measured.The investigation showed that the joints included three zones,base metal(BM),thermal mechanical affected zone(TMAZ) and welding zone(W).The TMAZ microstructure was similar to base metal,alpha and beta phase were elongated along the stress direction,recrystallization occurred in the weld zone.The induced microstructures were different from the BM.The maximum temperature can reach 1 270 ℃ which exceeds the titanium beta transformation temperature.the tensile test result showed that joint tensile strength was equal to that of the TC4 at room temperature and 200 ℃,while the testing temperature is 400 ℃,the joint tensile strength can reach 95% of the TC4 base mental.