A novel technique for development of A356/Al2O3 surface nanocomposite by friction stir processing

A356/Al2O3 surface nanocomposite was produced by friction stir processing (FSP). XRD, optical microscopy, SEM, microhardness and nanoindentation tests were used to characterise the samples. The results indicated that the uniform distribution of Al2O3 particles in the A356 matrix by FSP can improve the mechanical properties. The hardness and elastic modulus of the as-received A356, the sample treated by FSP without Al2O3 particles, surface microcomposite specimens and surface nanocomposite specimens were about 75 Hv and 74 GPa, 69 Hv and 73 GPa, 90 Hv and 81 GPa, 110 Hv and 86 GPa, respectively.