摘要
通过一系列工艺参数试验,获得无缺陷的T型接头焊缝。针对缺陷的形成,重点分析三种不同的搅拌针,即圆锥光针、圆锥螺纹针和短圆柱光针,对6 mm厚的6082-T6铝合金T型接头从内角角焊缝进行静轴肩搅拌摩擦焊接,并分析对应的焊缝产生的宏观缺陷。发现角接静轴肩搅拌摩擦焊容易在前进侧产生孔洞或沟槽缺陷。进一步分析发现,缺陷的产生受T接搅拌针和T接静轴肩的影响,在搅拌头周围,受T接静轴肩和T接搅拌针上部的影响,会形成搅拌针上部塑性流动区域,受搅拌针下部的影响,会形成搅拌针下部塑性流动区域.通过研究提出:搅拌针下部的孔洞缺陷可以通过采用螺纹的锥形搅拌针进行消除。而搅拌针上部的孔洞缺陷受到90°的T接静轴肩几何形状的影响流动能力较弱,通过倾角的改变可获得无缺陷的焊缝,并且对其缺陷形成机制的物理模型进行分析。
The defect free T-joints obtained by corner stationary shoulder friction stir welding. Three different pins, i.e. tapered pin, tapered pin with thread, short cylindrical pin, are used for friction stir welding of 6 mm thick 6082-T6 T-joint aluminum alloy from the inner corner weld, and corresponding analysis of the macro defects of the weld is carried out. It is found that the tunnel or groove defects are easily produced on the advancing side of the corner joint during friction stir welding. The defects are affected by the pin and corner stationary shoulder. The plastic material flow region on the upper part of pin will be formed around tool under the influence of the corner stationary shoulder and the upper part of the pin. The plastic material flow region on the lower part of the pin will be formed under the influence of the lower part of the pin. Besides, the tunnel defects on the upper part of the pin is affected by the stationary shoulder of 90°profile corner stationary shoulder, The defect free T-joints can be obtained by changing the tool tilt angle, and the physical model of the defect formation mechanism is analyzed.
作者
曾申波
陈高强
刘瞿
张弓
史清宇
ZENG Shenbo;CHEN Gaoqiang;LIU Qu;ZHANG Gong;SHI Qingyu(Department of Mechanical Engineering,Tsinghua University,Beijing 100084;Key Laboratory of Advanced Material Processing Technology,Ministry of Education of China,Tsinghua University,Beijing 100084)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2020年第6期193-199,共7页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(51705280,51375259)。
关键词
T型接头
角接静轴肩搅拌摩擦焊
倾角
缺陷
形成机制
T-joint
corner stationary shoulder friction stir welding
material flow
defects
formation mechanism
