Fabrication of Al/Al 2 o 3 Functionally Graded Material Using Powder Metallurgy Route

Six-layer (100Al, 90Al–10Al2O3, 80Al–20Al2O3, 70Al–30Al2O3, 60Al–40Al2O3, 50Al–50Al2O3 by vol. fraction) Al/Al2O3 Functionally Graded Material (FGM) each layer thickness ~1.5 mm was successfully synthesized by powder metallurgy route and the effect of Al2O3 volume fraction on microstructural and mechanical properties were studied. The graded powder layers were compacted and sintered using uni-axial hot press by simultaneous application of temperature and pressure at 400 ℃ & 10−5 mbar pressure. Experimental results revealed that relative density depends on sintering temperature and it varies from 2.67 × 103 to 2.71 × 103 kg/m3 with increase of sintering temperature from 400 to 450 ℃. The compacted sample shows increase of hardness with increase of Al2O3 volume fraction in the matrix from 35.2 HV to 74.8 HV of 100% Al and 50Al–50Al2O3 layers respectively. FESEM images of the cross section of the consolidated samples revealed that the layers are distinct and interface of layers are completely bonded with each other. The result also indicates that FGM fabricated by powder metallurgy method could be a better substitute for light weight and wear resistance application.