冰晶石对TC4激光焊焊缝成形和组织性能的影响  

Effect of cryolite on weld formation,microstructure and mechanical properties of TC4 laser welded seams

作　　者：武晓芳 侯继军[1] 董俊慧[1] WU Xiaofang;HOU Jijun;DONG Junhui(School of Materials Science and Engineering,Inner Mongolia University of Technology,Hohhot 010051,China)

机构地区：[1]内蒙古工业大学材料科学与工程学院,呼和浩特010051

出　　处：《内蒙古工业大学学报（自然科学版）》2024年第5期425-433,共9页Journal of Inner Mongolia University of Technology：Natural Science Edition

基　　金：内蒙古自治区高校基本科研业务费项目(JY20230027);内蒙古工业大学博士基金项目(BS2021001)。

摘　　要：为提高TC4钛合金焊接过程中对激光的吸收率,改善焊缝成形,选取冰晶石作为活性剂对TC4钛合金进行活性激光焊接,借助光学显微镜、X射线衍射仪、维氏硬度计、拉伸试验机、高速摄像机等分析了冰晶石对焊缝成形和接头组织性能的影响及作用机制。结果表明,冰晶石对焊缝表面成形无不良影响,可以增加焊缝熔深、改善焊缝截面尺寸。冰晶石对焊缝显微组织物相组成无显著影响,但会使焊缝上部和下部柱状晶的尺寸梯度减小,涂敷冰晶石后接头的性能不低于未涂敷接头。冰晶石可以作为TC4钛合金激光焊的一种有效活性剂,通过激光在其细小颗粒之间的多次反射,降低光致等离子体对激光的吸收和散射,提高吸收率。Cryolite was selected as the active agent for active laser welding of TC4 titanium alloy to improve the laser absorption rate and weld formation during the welding process.The influence of cryolite on weld formation,welded joint microstructure and properties and mechanism were analyzed using optical microscopy,X-ray diffraction,Vickers hardness tester,tensile testing machine,scanning electron microscopy,and high-speed camera.The results show that cryolite has no adverse effect on the surface formation of the weld seam,and can increase the weld penetration depth and improve the cross�sectional size of the weld seam.Cryolite has no significant effect on the microstructure and phase composition of the weld seam,but it can reduce the size gradient of columnar crystals in the upper and lower parts of the weld seam;The performance of the welded joints coated with cryolite is not inferior to that of the uncoated joint,and cryolite can be used as an effective active agent for TC4 titanium alloy laser welding.Cryolite improves TC4 titanium alloy absorption rate by multiple reflections of laser light between its small particles and reducing the absorption and scattering of laser by photoinduced plasma.

关 键 词：冰晶石 TC4钛合金 焊缝成形 显微组织 光致等离子体 

分 类 号：TG456.7[金属学及工艺—焊接]