Modelling and Microstructure of Friction Stir Welds of AA2014 Alloy: Different Tool Pin profiles

Abstract In this work, the effect of different tool pin profiles such as triangle, square, pentagon and hexagon on friction stir welded butt joints of AA2014-T6 aluminium alloy using modelling and microstructure was investigated. Microstructure, mechanical properties and micro-hardness of all tool pin profiles are presented. The developed analytical heat generation models for different tool pin profiles are in good agreement with experimental results. From the developed models, sub-grain size at tool pin periphery using analytical modelling was almost corroborates with measured values. Smallest sub-grain size, high value of Zener-Holloman parameter and lowest peak temperature at tool pin periphery produced using square tool pin profile are the key mechanisms for improved friction stir welded joint properties.