Effects of Post-Weld Heat Treatment on the Microstructureand Mecanical Properties of the AZ91 Laser Welded Joint

Archives of Metallurgy and Materials

article

A. Dziadoń¹  E. Musiał¹ 

[1] Kielce University of Technology, Metals Science and Materials Technologies

关键词: AZ91 alloy;    laser welding;    heat treatment after welding;   

DOI  :  10.24425/amm.2022.137774

学科分类：物理（综合）

来源: Akademia Gorniczo-Hutnicza im. Stanislawa Staszica / University of Mining and Metallurgy

【 摘 要 】

Plates of AZ91 magnesium alloy were butt-welded using a CO2 laser. The non-equilibrium solidification of the laser-meltedmetal caused fragmentation of the weld microstructure as well as the supersaturation of a solid solution of aluminium in magnesium, which enabled the T5 ageing of the weld. The weld proved to be a mechanically stable part of the joint; all the tensile-testedspecimens, both as-welded and post-weld T5 aged, fractured outside it. During the ageing of the supersaturated joint, which involved heat treating it to the T6 condition, the weld was the region where discontinuous precipitation was observed and this wasthe location of fracture in the tensile specimens. Thus, the strength properties of welded, supersaturated and aged AZ91 were muchworse than when the non-welded material was T6 tempered.

【 授权许可】

CC BY-NC