Research on Work Hardening Type Superplastic Deformation Behavior of FSW Titanium Alloy

Abstract:

The combination of FSW and SPF processing is one of most attractive fabrication method for the larger structures and integrate substructure to reduce the part count of aircraft assemblies and costs. One purpose of the SPF technology development is to decrease the forming temperature and increase the forming rate, then reduce cost and enhance the efficiency. Maybe FSW could supply another way to achieve this besides reduce the grain size by traditional rolling process. The purpose of this study is to indicate some new results of the superplasticity of weld nugget for the Ti-6Al-4V alloy. It is found that the temperature has no much effects on the superplastic tensile elongation of the weld nugget, and deformation rate has the contrary effects on the superplasticity to the traditional results, the elongation will be higher with the higher deformation rate. The mechanism will be discussed with the analysis of the microstructure by SEM. The tensile properties was tested after SPF process with a 60% strain.

• Periodical: Materials Science Forum (Volumes 838-839)
• Pages: 506-511
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.838-839.506
• Online since: January 2016
• Authors: Ming Jie Fu*, Xiao Hua Li, Xiu Quan Han, Hui Yuan Xu
• Keywords: FSW, Microstructure, Superplasticity, Titanium Alloy, Work Hardening

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