LAUSR

Abstract This work investigates the effect of Al2O3 and ZrO2 addition on microstructure and mechanical properties of Ni based functionally graded composites (FGCs). The cylindrical pellets of different compositions of three layered FGCs were prepared through mechanical alloying followed by compaction and conventional sintering. The sintering was conducted at 1200 °C for 90 min under vacuum atmosphere. Microstructure, hardness and flexural strength of the samples were examined and comparisons were made between Al2O3 and ZrO2 alloying. The FGCs with alloying of Al2O3 along with ZrO2 shows the highest hardness of 258.1 HV0.05. The flexural strength of FGCs improved to 18% by combined alloying of Al2O3 and ZrO2. The homogeneous dispersion of refined powder particles and precipitation of Al–Zr–O oxides appears to be responsible for the improved properties of Ni based FGCs.