模拟烧伤温度对TC4-DT钛合金组织与性能的影响

采用光学显微镜(OM)、透射电镜(TEM)、显微硬度计和万能拉伸试验机等方法研究了飞机用TC4-DT钛合金材料在4种模拟烧伤温度(850、950、1050、1150℃)下的组织、强度、硬度和电阻的变化情况,并给出了快速烧伤检测的方法.结果表明:当模拟烧伤温度为850℃时,合金等轴组织主要由α相+少量β相组成,随着模拟烧...

Effect of simulative burn temperature on microstructure and properties of TC4-DT titanium alloy

The changes of microstructure, strength, hardness and sheet resistance of TC4-DT titanium alloy after burned at four simulative temperatures (850, 950, 1050 and 1150 ℃) were studied by using optical microscope (OM), transmission electron microscope (TEM), microhardness tester and universal tensile testing machine, and a rapid method for burn detection was given. The results show that when the simulative burn temperature is 850 ℃, the alloy equiaxed structure is composed of α phase and a small amount of β phase, and the equiaxed structure will be coarsened with the increase of temperature to 950 ℃. When the simulative burn temperature is 1050 ℃, the grain size increases remarkably and the structure gradually becomes lamellar, with the decrease of primary α phase, the increase of β phase and the precipitation of secondary α phase. With the change of simulative burn temperature to 1150 ℃, the lamella structure will continue to be coarsened. The degree of burn is related to the resistance, strength and hardness of the alloy. With the increase of simulative burn temperature, the sheet resistance increases monotonously, the strength decreases, and the hardness first decreases and then increases. Therefore, the burn degree of titanium alloy can be determined by measuring the sheet resistance.