Effect of pulsation in TIG welding on the microstructure, residual stresses, tensile and impact properties of Ti-5Al-2.5Sn alloy

Research output: Contribution to journalArticlepeer-review

Authors

Colleges, School and Institutes

External organisations

  • Ghulam Ishaq Khan Institute of Engineering Sciences and Technology
  • Pakistan Welding Institute

Abstract

Pulsation of current is widely employed in Tungsten Inert Gas (TIG) welding of titanium alloys. In the current study, the influence of welding speed and welding currents (peak and background) on the properties pulsed TIG welded Ti-5Al-2.5Sn alloy were investigated. The weldment characteristics which were analyzed included weld zone size, microstructure, residual stresses, tensile and impact properties. Increasing the welding speed and gradient of pulsed current enhanced grain strengthening in the fusion zone (FZ) which was attributed to increased cooling rate. Such a welding condition was also favorable in achieving full penetration weldments with a reduced; heat affected zone width, grain size in FZ and residual stresses. However, a tensile strength superior to the base metal was observed. The impact toughness reduced by increasing the pulsed current gradient and a high value of both peak and background currents were required to improve the impact toughness of the weldments.

Bibliographic note

Funding Information: The authors wish to thank Pakistan Welding Institute and Pakistan Institute of Engineering and Applied Sciences for use of research facilities. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The authors would like to thank Ghulam Ishaq Khan Institute of Engineering Sciences and Technology for providing funding for this project. Publisher Copyright: © IMechE 2020.

Details

Original languageEnglish
Pages (from-to)361-370
Number of pages10
JournalProceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering
Volume235
Issue number2
Early online date7 Oct 2020
Publication statusPublished - 1 Apr 2021

Keywords

  • grain boundaries, impact toughness, microstructure, residual stress, Titanium alloys, tungsten inert gas welding