Effect of friction stir processing on the microstructure of pure magnesium castings

Abstract

In this paper, the effects of the pin profile and its rotational speed on material flow, microstructure, hardness and grain orientation of the friction-stirred pure Mg castings were investigated. For this purpose, three different tool pin profiles (non-threaded cylindrical, threaded cylindrical and conical) were used with various tool rotational speeds. The material flow, refining and grain growth of the material during the friction stir processing was monitored and then related to the Zener-Hollomon parameter. The grain orientation distribution was also investigated using X-ray diffraction.