2mm厚TC4钛合金激光焊接接头组织与力学性能研究

Study on Microstructure and Mechanical Properties of Laser Welded Joint of 2mm Thick TC4 Titanium Alloy

为了实现钛合金高质量焊接,以2 mm厚TC4钛合金为试验材料,采用YAG激光焊接方法进行了实验研究,获得了成形良好的焊接接头,分析了焊接接头微观组织、力学性能。结果表明,在激光焊接过程中,由于焊缝冷却速度较快,随着到焊缝中心距离的增加,接头组织晶粒尺寸逐渐减小,硬度分布逐渐降低,焊缝中心以等轴晶为主;接头的抗拉测试断于母材,说明焊缝的力学性能不低于母材,可在相关工程中推广应用。

In order to realize high quality welding of titanium alloy,the experiment was carried out with 2 mm thickness TC4 titanium alloy by YAG laser welding.The welded joint with good shape was obtained,and the microstructure and mechanical properties were analyzed.The results show that in the laser welding process,due to the faster cooling rate of the weld,as the distance to the center of the weld increases,the grain size of the joint structure gradually decreases,and the hardness distribution gradually decreases,the center of the weld is dominated by equiaxed crystals;The tensile test of the joint is broken at the base material,indicating that the mechanical properties of the weld are not lower than the base material,which can be promoted and applied in related projects.