Study on Defects of T-joints by Corner Stationary Shoulder Friction Stir Welding

doi:10.3901/JME.2020.06.193

Abstract

Abstract: 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.

Key words: T-joint, corner stationary shoulder friction stir welding, material flow, defects, formation mechanism

CLC Number:

TG453

ZENG Shenbo, CHEN Gaoqiang, LIU Qu, ZHANG Gong, SHI Qingyu. Study on Defects of T-joints by Corner Stationary Shoulder Friction Stir Welding[J]. Journal of Mechanical Engineering, 2020, 56(6): 193-199.

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