Synthesis and Characterization of Functionally Graded Al-6Cr-Y2O3 Composites

The present investigation aims at fabricating a functionally graded Al-6Cr-Y₂O₃ composite and its microstructural and property characterization. Al-6Cr-alloys with varying percentage of Y₂O₃ (5-10 vol. %) have been used to fabricate FGM by powder metallurgy route. The samples were subsequently subjected to solution treatment at 610°C for 4h followed by artificially aged at 310°C for 4h. The microstructure, hardness and wear behavior of these FGM have been evaluated. FGM exhibited superior hardness (360 ± 5 VHN) as compared to the unprocessed composites (220 ± 5 VHN) due to the uniform dispersion of Y₂O₃ particles. Wear resistance of Al-6Cr-10Y₂O₃ FGM were compared that of with pure Al-6Cr alloy by dry abrasive wear test. Al-6Cr-10Y₂O₃ FGM composites were found to exhibit higher wear resistance with the minimum wear rate of 0.009 mm³/m compared to the Al-6Cr alloy wear rate 0.02 mm³/m.