论文部分内容阅读
通过拉伸试验、硬度测试及金相分析等方法,对TC15钛合金激光焊接接头的显微组织和力学性能进行研究。结果表明,焊缝的深宽比在4~6之间波动,焊缝区域的晶粒形貌为柱状结构,且从焊缝中心线往外呈对称分布状态,主要为β相大晶粒。热影响区组织由细晶区、粗晶区及再结晶区构成,熔合线附近区域的晶粒明显粗化。焊缝区具有相对稳定的硬度值分布,硬度与热影响区的粗晶区相近。较低焊接电流焊缝试样具有最低的抗拉强度,其断裂部位为焊缝区;随着焊接电流的增大,焊接接头抗拉强度得到提高。
The microstructure and mechanical properties of TC15 titanium alloy laser welded joints were studied by means of tensile test, hardness test and metallographic analysis. The results show that the aspect ratio of the weld fluctuates between 4 and 6, and the grain morphology in the weld zone is columnar structure with a symmetrical distribution from the centerline of the weld, which is mainly β-phase large grains. The HAZ consists of a fine grain region, a coarse grain region and a recrystallized region, and the grains in the vicinity of the fusion line are significantly roughened. Weld zone has a relatively stable distribution of hardness values, hardness and heat affected zone coarse grain area similar. The weld with lower welding current has the lowest tensile strength and the fracture site is the weld zone. With the increase of welding current, the tensile strength of welded joint is improved.