J. Mater. Sci. Technol. ›› 2018, Vol. 34 ›› Issue (1): 198-208.DOI: 10.1016/j.jmst.2017.11.024

Special Issue: Titanium Alloys 2018 FSW-and-FSP-articles 2018

• Orginal Article • Previous Articles     Next Articles

Variant selection in stationary shoulder friction stir welded Ti-6Al-4V alloy

Xiaoqing Jianga*(), Bradley P. Wynneb, Jonathan Martinc   

  1. a Engineering Research Center of Advanced Manufacturing Technology for Automotive Structural Parts, Ministry of Education, College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China
    b Department of Materials Science and Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, S1 3JD, UK
    c The Welding Institute, Granta Park, Great Abington Cambridge, CB21 6AL, UK
  • Received:2017-03-21 Revised:2017-06-01 Accepted:2017-06-03 Online:2018-01-20 Published:2018-02-09
  • Contact: Jiang Xiaoqing

Abstract:

Stationary shoulder friction stir welding of Ti-6Al-4V of 7 mm thickness was conducted with varying welding speeds and rotation speeds. Variant selection analysis was carried out based on the inherited α phase texture and the reconstructed β phase texture. The weld surfaces became significantly smoother with increasing welding speed and decreasing rotation speed. Heat input decreased greatly with increased welding speed and it decreased slightly with decreased rotation speed. The orientation relationship between the prior β grains was measured based on the reconstructed electron backscattered diffraction (EBSD) data. Weak Variant selection has occurred in all the welds because most of the prior β grains did not share {110} poles. Strong links between crystal orientation of the prior β grains and hardness have been found.

Key words: Stationary shoulder friction stir welding, Texture, Variant selection, Hardness