Overview of the Effect of Post Welded Heat （概述焊接后热的影响）.pdf

ISSN: 2277-3754 ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT) Volume 2, Issue 9, March 2013 Overview of the Effect of Post Welded Heat Treatment on Friction Stir Welding Of Aluminum Alloys M. Muthu Krishnan when alloys are not sensitive to strain hardening [3]. Abstract :-The objective of this investigation is to learn However, non-heat treatable and sensitive to strain how and why certain alloys (primarily Aluminum alloys) can hardening aluminum alloys exhibit softening in weld be strengthened by Precipitation Hardening heat treatment zone owing to decrease in dislocation density [4]. Most of processes and their effects on the friction stir weldments of the earlier studies on friction stir welding of similar type Aluminium alloys. The strength and hardness of some metal alloys may be enhanced by the formation of extremely small of Al alloys are confined in evaluating stirring zone uniformly dispersed particles of a second phase within the microstructure, micro-hardness and bond strength [5]. original phase matrix; this must be accomplished by appropriate heat treatment. The process is called Precipitation II. PRINCIPLES OF PRECIPITATION Har