Hits:

Affiliation of Author(s):材料科学与技术学院

Title of Paper:Dissimilar friction stir welding of aluminum alloys adopting a novel dual-pin tool: Microstructure evolution and mechanical properties

Journal:JOURNAL OF MANUFACTURING PROCESSES

Key Words:Friction stir welding Materials mixing Microstructure Mechanical Properties

Abstract:To improve the degree of materials mixing in dissimilar Friction Stir Welded (FSW) joints and mechanical properties, a novel stirring tool with dual-pin structure was designed and used to perform welding AA 2024 to AA6061 aluminum alloy plates with butt configuration. The microstructure and mechanical properties of the joints fabricated by single-pin and dual-pin tools were studied using optical microscope (OM), scanning electron microscope (SEM), microshardness tester and tensile testing machine. It was found that joints produced by dual pin tool were all free of defects throughout the selected parameters, but for the joints produced by single-pin welded joints, void defects were produced at welding speed higher than 90 mm/min. All the nugget regions of dual-pin joints were characterized by typical onion ring patterns which were absent in those obtained by dual pin tool. The highest ultimate tensile strength (UTS) of 242 MPa was obtained with the dual-pin tool at welding speed of 150 mm/min, while for the case of single-pin the best joint was obtained at welding speed of 90 mm/min. For the defect free joints, those produced by dual-pin tool showed more uniform microhardness distribution over the cross section of joints than the ones produced by single-pin tool.

ISSN No.:1526-6125

Translation or Not:no

Date of Publication:2018-12-01

Co-author:Hou, Wentao,Huang, Guoqiang,Yan, Yinfei,gcl,Li, Junping

Correspondence Author:SHEN Yifu