Effect of pin profile volume ratio on microstructure and tensile properties of friction stir processed aluminum based metal matrix composites

摘要

AbstractMetal Matrix Composites (MMCs) fabricated via stir casting route are found to have inherent defects such as porosity which deteriorates the mechanical properties. In this investigation, friction stir processing (FSP), an adaptation of friction stir welding (FSW) was used to reduce the level of Porosity of LM25 aluminium alloy matrix with 5% SiC particulates fabricated via stir casting. The pin profile volume ratio (dynamic volume of pin/static volume of pin) plays a vital role in FSP since the actual stirring action and material consolidation are influenced by this parameter. Hence, in this work an attempt has been made to study the effect of pin volume ratio of four different tool pin profiles, namely, straight cylindrical (STC), tapered cylindrical (TAC), threaded cylindrical (THC) tapered threaded cylindrical (TTC). Tensile specimens were extracted from the FSPed area and the tensile properties were evaluated. The micro hardness of the FSPed region was also measured using Vickers hardness tester. From the results it is found that the FSP region produced by tapered cylindrical pin profile exhibited superior tensile properties and hardness compared to its counterparts.Highlights?Friction stir process (FSP) were used to fabricate LM25AA-5% SiCp metal matrix composite.?Pin volume ratio is one of vital parameter which will influence the processing efficiency predominantly.?Influence of Pin volume ratio in the SiC particle breakup and distribution of particles were investigated.?FSP can overcome the above said problem and capable of result friction stir processed zone of better properties.]]>