Effect of tool pin profile on distribution of reinforcement particles during friction stir processing of B4C/aluminum composites

Boron carbide /aluminum composites have been produced on an aluminum-silicon cast alloy using friction stir processing. Effect of pin profile on the distribution of boron carbide in the stir zone of the friction stir processed specimens was investigated experimentally and numerically. The material flow generated by the threaded and circular tool pin profiles, being the main reason for the distribution of particles in the metal matrix, was numerically modeled using a thermomechanically coupled three-dimensional finite element model. Numerical and experimental results show that threaded pin profile produces a more uniform distribution of B4Cp than other pin profiles. Hardness tests were performed in order to investigate mechanical properties of the composites. Wear resistance of the composite was evaluated and obtained results showed that the hardness and wear resistance of the composite significantly improved.