基于田口方法的AZ31镁合金搅拌摩擦点焊工艺参数优化  

Parameters optimization of the friction stir spot welding for AZ31 magnesium alloy based on Taguchi orthogonal array

作　　者：陈松林[1] 张大童[1] 张文[1] 邱诚[1] 

机构地区：[1]华南理工大学国家金属材料近净成形工程技术中心,广东广州510640

出　　处：《电焊机》2015年第11期78-83,共6页Electric Welding Machine

基　　金：中央高校基本科研业务费专项资金资助项目(2014ZG0028);高等学校博士学科点专项科研基金资助项目(20130172110044)

摘　　要：按照正交表对9组AZ31镁合金搭接试样进行搅拌摩擦点焊,采用田口方法对接头的力学性能进行了信噪比和方差分析。结果表明,搅拌摩擦点焊工艺参数对接头最大拉伸载荷影响由大到小依次为旋转速度、停留时间和压下量。在1 000 r/min旋转速度、5 s停留时间、4.6 mm下压量条件下,得到的接头具有最大的拉伸力。组织和硬度分析表明,拉伸承载能力最强的试样冶金结合区和拉伸变形量最大,但硬度值最低。拉伸断口形貌分析表明,点焊接头断裂方式均为韧-脆混合型断裂。The friction stir spot welding is used for nine sets of AZ31 magnesium alloy lapping specimens aecording to the orthogonal table. The Signal to Noise Ratio （SNR） and variance analysis of the mechanical properties of the welded joints are tan＇led out by the Taguchi methods. The results show that the descending sequence of influence of friction stir spot wehting parameters on the maximum tensile load of joints is tool rotational speed,dwell time, plunge depth. The optimized parameters include tool rotational speed of 1 000 r/min,dwell time of 5 s,and plunge depth of 4.6 mm. According to the microstructure and microhardness tests,the specimen with maximum tensile load has the largest size of metallurgical bond zone and the largest tensile deformation value,however,the lowest hardness value of the SZ zone. SEM tensile fracture morphologies indicate that the wehted joints fracture in a mixture mode of ductile and brittle fracture in this experiment.

关 键 词：AZ31镁合金 搅拌摩擦点焊 田口方法 参数优化 

分 类 号：TG453.9[金属学及工艺—焊接]