摘要
传统镁合金搅拌摩擦焊接过程中材料流动性能较低,从而焊缝容易出现缺陷。本文利用COMSOL仿真软件,建立一种镁合金载流静轴肩搅拌摩擦焊(SSFSW)双热源数值模型,研究输入电流对材料流动性能的影响。通过改变输入电流参数进行数值模拟得到焊接过程温度场,应力场和速度场的演变规律。发现随着电流的提高,温度场分布沿焊缝厚度方向趋于均匀化,焊缝的温度梯度降低,应力场峰值从532 MPa降低至461 MPa,呈明显降低趋势,证明此时焊缝中材料流动性得到显著提高。在电流达到150 A时,焊接温度峰值接近于材料熔点650℃,在此温度下易于得到无缺陷的焊缝和性能优异的焊接接头。数值模拟有效地预测实际焊接实验中可能会出现的结果,减少为了得到合理焊接参数所需大量实验的成本,并且仿真结果对工艺参数的选择有重要的指导意义。
In the traditional magnesium alloy friction stir welding process,the material flow performance is low,so the weld is prone to defects.In this paper,COMSOL simulation software was used to establish a dual heat source numerical model for magnesium alloy current-carrying static shaft shoulder friction stir welding(SSFSW),and the influence of input current on material flow performance was studied.The evolution law of temperature field,stress field and velocity field in welding process was obtained by numerical simulation by changing the input current parameters.The results show that with the increase of the current,the temperature field distribution tends to be homogenized along the direction of the weld thickness,the temperature gradient of the weld decreases,and the peak stress field decrease from 532 MPa to 461 MPa,showing an obvious decreasing trend,which proves that the material liquidity in the weld is significantly improved at this time.When the current reaches 150 A,the peak welding temperature is close to the melting point of the material at 650℃.At this temperature,it is easy to get the weld without defect and the welded joint with excellent performance.The numerical simulation can effectively predict the possible results in actual welding experiments,reduces the cost of a large number of experiments in order to obtain reasonable welding parameters,and the simulation results will have important guiding significance for the selection of process parameters.
作者
陈树君
王磊
蒋晓青
王奕琳
袁涛
CHEN Shu-jun;WANG Lei;JIANG Xiao-qing;WANG Yi-lin;YUAN Tao(College of Mechanical Engineering and Applied Electronics Technology,Beijing University of Technology,Beijing 100124,China)
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2021年第7期1786-1797,共12页
The Chinese Journal of Nonferrous Metals
基金
国家重点研发计划资助项目(2018YFB1306400)
国家自然科学基金资助项目(51604015)
北京市基础科学研究基金资助项目(PXM2019_014204_500032)。
关键词
AZ31镁合金
载流静轴
肩搅拌摩擦焊
数值模型
温度场
应力场
AZ31B magnesium alloy
electric assisted stationary shoulder friction stir welding
numerical mode
temperature field
stress field
作者简介
通信作者:蒋晓青,讲师,博士,电话:010-67392667,E-mail:xjiang@bjut.edu.cn。
