激光焊接ZL114A/5A06 异种铝合金接头组织及性能

采用激光焊接ZL114A/5A06异种铝合金,通过参数优化以获得性能优良的焊接接头,利用光学显微镜(OM)、拉力试验机、高温疲劳试验机、SEM和EDS对接头的显微组织、力学性能和拉伸断口进行了研究。结果表明:焊缝中心区的金相组织为等轴晶;接头焊后不经热处理,抗拉强度可达到265 MPa,为母材强度的80%以上,并有很好的抗疲劳性能;断口分析显示断裂位置在ZL114A母材一侧的熔合线附近;在保证焊透的前提下,激光功率越小,晶粒越细小,接头强度越高。对框架蒙皮结构铝合金贮箱产品试验件进行了焊接,试验件达到了产品各项性能指标要求。

Microstructure and Properties of Dissimilar Aluminum Alloys ZL114A/5A06Joints by Laser Welding

Excellent ZL114A/5A06 joints by laser welding were obtained after parameter optimization. The microstructure,tensile strength and tensile fracture were analyzed by means of optical microscopy(OM), tensile testingmachine,high temperature fatigue testing machine,scanning electron microscopy( SEM) and energy dispersive Xrayspectrometry(EDX). The results show that the microstructure of the central welding zone is equiaxed crystal. The average tensile strength of untreated welding joints can reach 265 MPa,which is more than eighty percent of that of basemetal,excellent fatigue resistance of the joints is also demonstrated. The fracture appears near the fusion line ofZL114A,and under the premise of full weld penetration,the lower laser power, the smaller crystal size and the highertensile strength. Aluminum alloy conduithead with stressedskin construction was successfully welded and can meetthe requirements.