Abstract:

Al 5083/10 wt% SiC_p nano composites have been synthesized by means of high energy ball milling followed by spark plasma sintering (SPS). Nano composites produced via this method exhibited near-theoretical density while retaining the nano-grained features. X-ray diffraction (XRD) analysis indicated that the crystalline size of the ball milled Al 5083 matrix was observed to be ~25 nm and it was coarsened up to ~30 nm after SPS. Nano indentation results of nano composites demonstrated a high hardness of ~280 HV with an elastic modulus of 126 GPa. Wear and friction characteristics with addition of SiC_p reinforcement exhibited significant improvement in terms of coe±cient of friction and specific wear rate to that of nano structured Al 5083 alloy. The reduction in specific wear rate in the nanocomposite was mainly due to the change of wear mechanism from adhesive to abrasive wear with the addition of SiC_p which resulted in high hardness associated with nano-grained microstructure.

Key words: Metal matrix nano composites , Friction/wear , Mechanical properties ,  High resolution transmission electron microscopy ,  Spark plasma sintering ndentation