Studies on effect of friction stir welding process parameters on weld quality of al sicp metal matrix composites

Abstract

Aluminium based Metal Matrix Composites (MMCs) have very newlinegood mechanical properties, such as higher strength, higher hardness, and newlinehigher wear resistance, but their applications in industries are restricted newlinemainly due to the non-availability of suitable welding techniques. The main newlinedifficulty in the fusion welding of Al/SiCp Metal Matrix Composites (MMCs) newlineis the occurrence of segregation and deleterious reactions, between the newlinereinforced particles and liquid aluminum in the fusion zone. However, the newlinefriction stir welding process (FSW) is a suitable process to join the materials. Friction stir welding (FSW) is an emerging solid state joining newlineprocess, in which the material that is being welded does not melt and recast. newlineHowever, FSW joints are prone to defects like pin hole, tunnel defect, piping newlinedefect, kissing bond, cracks etc., due to the improper flow of the metal and its newlineinsufficient consolidation in the weld nugget region. The published literature newlinefocusing on the effect of FSW process parameters, on the formation of defect newlinefree weld nugget zone in aluminium based MMCs is very limited. Hence, the newlinepresent investigation was carried out to study the effect of the FSW process newlineparameters on the formation of a defect free weld nugget zone, as well as on newlinethe tensile properties of the welded joints of Al/SiCp MMCs. In this investigation, an attempt was made to study the effect of the newlineheat input on the evolution of the microstructure in the weld region of the newlinefriction stir welded aluminum alloy. AA6061-10% SiCp and AA6061-20% newlineSiCp MMCs were used as the base materials. A square butt joint newlineconfiguration from rolled plates of 6 mm thickness was prepared to fabricate newlinethe FSW joints. Non-consumable tools made of high speed steel were used to newlinefabricate the joints. Nearly 105 joints were fabricated to study the effect of the newlineFSW process parameters, such as the tool rotational speed, welding speed and newlineaxial force on the tensile properties of the friction stir welded MMCs. newline