高镁铝合金焊接接头软化机制研究及软化模型的建立  

Study on Softening Mechanism and Establishment of Softening Model of Welding Joint of High Magnesium Aluminum Alloy

作　　者：胡铭汇 赖少波 郑文健 冯道臣 闫德俊 王宇 王文军 俞臻 杨建国 HU Minghui;LAI Shaobo;ZHENG Wenjian;FENG Daochen;YAN Dejun;WANG Yu;WANG Wenjun;YU Zhen;YANG Jianguo(College of Mechanical Engineering,Zhejiang University of Technology,Hangzhou 310023,China;Guangdong Provincial Key Laboratory of Advanced Welding Technology for Ships,CSSC Huangpu Wenchong Shipbuilding Company Limited,Guangzhou 510715,China;Foshan University,Guangdong Provincial Key Laboratory of Advanced Welding Technology for Ships,Foshan 528000,China)

机构地区：[1]浙江工业大学机械工程学院,浙江杭州310023 [2]中船黄埔文冲船舶有限公司广东省舰船先进焊接技术企业重点实验室,广东广州510715 [3]佛山大学广东省舰船先进焊接技术重点实验室,广东佛山528000

出　　处：《电焊机》2024年第12期8-15,共8页Electric Welding Machine

基　　金：国家自然科学基金项目(52375391);浙江省“尖兵”“领雁”研发攻关计划项目(2023C01244)。

摘　　要：为了研究高镁铝合金焊接接头的软化机制并建立其焊接软化模型,采用显微硬度测试和微观表征方法对船用高镁铝合金平板MIG焊对接接头进行分析,揭示了软化主要源于固溶强化和弥散强化的减弱。随着焊接峰值温度的升高,Mg元素固溶于晶粒中,导致晶粒畸变减小,阻碍晶格位错运动的能力下降,从而削弱了固溶强化效果。高温下Mg元素从Al基体中蒸发出并偏聚在晶界处,形成Mg富集相,降低了弥散强化效果。基于硬度变化与焊接过程中的峰值温度,建立了软化程度随焊接峰值温度变化的软化模型,并通过有限元计算验证了其准确性。In order to study the softening mechanism of high magnesium aluminum alloy welded joints and establish their weld‐ing softening model,through microhardness testing and microscopic characterization,it is revealed that the softening mainly originates from the weakening of solid solution strengthening and dispersion strengthening.As the peak welding temperature increases,the Mg element dissolves in the grains,leading to a decrease in grain distortion and a decline in the ability to hinder lattice dislocation movement,thereby weakening the effect of solid solution strengthening.At high temperatures,the Mg element evaporates from the Al matrix and segregates at the grain boundaries,forming Mg-rich phases,which reduces the effect of dis‐persion strengthening.Based on the hardness changes and the peak temperature during the welding process,a softening model that varies with the peak welding temperature was established,and its accuracy was verified through finite element calculations.

关 键 词：高镁铝合金 软化机制 固溶强化 弥散强化 软化模型 

分 类 号：TG457.14[金属学及工艺—焊接]