Material Engineering and Mechanical Manufacturing

Weld formation and material flow behavior in FSW thick aluminum alloy plates

  • MAO Yuqing ,
  • KE Liming ,
  • LIU Fencheng ,
  • CHEN Yuhua
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  • 1. National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology, Nanchang Hangkong University, Nanchang 330063, China;
    2. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China

Received date: 2016-01-11

  Revised date: 2016-03-02

  Online published: 2016-03-11

Supported by

National Natural Science Foundation of China (51265043, 51265042); Landed Plan of Science and Technology in Colleges and Universities of Jiangxi Province (KGLD13055, KJLD12074)

Abstract

7075-T6 aluminum alloys of a thickness of 20 mm are friction stir welded using a tapered pin with three flats, and the effect of process parameters on weld formation and local flow characteristic are investigated. With the increase of the rotation speed, the area of nugget increases due to the increase of the amount of plastic metal migration in unit time, and the area of loose zone decreases and even disappears. When the rotation speed is too high, the loose defect emerges again. Decreasing the welding speed appropriately can improve the weld quality by increasing the heat input in unit length, and the defect is gone. A lower welding speed causes a bigger loose zone and many internal voids because of more heat input. In the welding under appropriate parameters, more plastic materials horizontally migrate around the rotary pin with the appearance of the temporary cavity, and the "sucking-extruding" effect along the horizontal direction can thus be enhanced, improving the flowability and eliminating the internal defects.

Cite this article

MAO Yuqing , KE Liming , LIU Fencheng , CHEN Yuhua . Weld formation and material flow behavior in FSW thick aluminum alloy plates[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2016 , 37(11) : 3546 -3553 . DOI: 10.7527/S1000-6893.2016.0061

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