TENSILE BEHAVIOUR AND FRACTOGRAPHY ANALYSES OF LM6/ZrO2 COMPOSITES

Aluminium-based metal matrix (LM6) composite materials were prepared using various percentages of 0 %, 3 %, 6 %, 9 % and 12 % of zirconia by the weight fraction method and fabricated by the stir casting method. Five samples were prepared as per the ASTM B-557-M-94 standard, and then the prepared sample was subjected to an energy-dispersive spectrometry (EDS), hardness and tensile tests. The hardness and tensile test results revealed that the maximum hardness, maximum ultimate strength, yield strength was obtained for the composite containing 12 % of mass fractions of ZrO2. The percentage of increase in zirconia increases the hardness, ultimate strength, yield strength. The minimum percentage of zirconia gives the minimum hardness and ultimate strength. Then EDS test was conducted on prepared samples. It was confirmed that aluminium and zirconia particles are present in the metal matrix composites. Fractography analysis was also employed in this work to understand the fracture mechanics of the surface. The fractography analysis was conducted with a scanning electron microscope (SEM). From the fractography analysis it was revealed that the nature of the fracture surface was changed from ductile with a large dimple surface to brittle fracture.