Influence of Heat Index on Tensile Properties and Formability of Friction Stir Dissimilar Welded Blanks

Abstract

In friction stir welding process, developed heat is considered as an important factor because it strongly influences the properties of welding. In this study, the effect of heat index on tensile properties and forming behaviour of friction stir welded joints were studied. The influence of grain size on the hardness is also studied. Microhardness and grain size relationship of the welded blanks is expressed in the Hall–Petch equation. It was observed that the mechanical properties and hardness were better at lower rotational speed. An improved formability is achieved at the lower tool rotational speed rather than the high rotational speeds due to refinement of grains occurred at lower heat input.