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利用光纤激光对激光熔化沉积TC17钛合金与锻造TC17钛合金薄板进行了激光热导熔化焊接,利用光学显微镜、扫描电镜、X射线衍射仪和显微硬度计分析了接头的组织结构及显微硬度分布。结果表明,TC17钛合金激光熔化沉积件及锻件薄壁板状试样激光焊接接头凝固组织为沿未熔母材外延定向生长的细小树枝晶组织。锻造钛合金焊缝热影响区(HAZ)大且热影响区β晶粒发生了严重的长大现象,而激光熔化沉积钛合金焊缝热影响区小且热影响区β晶粒尺寸几乎无明显变化,表现出优异的焊接热稳定性。无论锻造钛合金还是激光熔化沉积钛合金,其焊缝区显微硬度高于母材,热影响区显微硬度低于母材。
The fiber laser was used to laser weld the TC17 titanium alloy and the forged TC17 titanium alloy plate. The microstructure and microhardness of the joint were analyzed by optical microscope, scanning electron microscope, X-ray diffraction and microhardness tester distributed. The results show that the solidified microstructure of laser welded joints of TC17 titanium alloy and forged thin-walled plate specimens are fine dendrites grown epitaxially along the base material. However, the heat-affected zone (HAZ) and the heat-affected zone (HAZ) of the as-welded Ti alloy had a serious growth of β-grains. However, the HAZ of the laser-melted-deposited titanium alloy was small and the β-grain size of the HAZ was almost insignificant Changes, showing excellent thermal stability of the weld. Both forged titanium alloy and laser-melted titanium alloy, the microhardness of the weld zone is higher than that of the base metal, and the microhardness of the heat-affected zone is lower than that of the base metal.