Fabrication of Nanostructured Y2O3, Y2O3-Al2O3, Y2O3-TiO2, Y2O3-Cr2O3 Ceramic Oxides for Structural Applications

Abstract

Ceramic oxides of Y2O3(Y), Y2O3-50Al2O3(YA), Y2O3-50TiO2 (YT), Y2O3-50Cr2O3(YC) (in weight%) are fabricated by mechanical alloying for 20 h, followed by hydrogen sintering at 1300 degrees C with a holding time of 30 min. The powder microstructure at 20 h of milling is investigated by high-resolution transmission electron microscope (HRTEM). No distortion and shrinkage of the samples sintered in the hydrogen atmosphere have been observed. The x-ray diffraction study reveals the presence of mixed oxide Al5Y3O12, Y2Ti2O7, YCrO3 in YA, YT, YC samples, respectively. Maximum relative sintered density of 89.98% has been achieved in YT sample. YT sample also records the highest microhardness (644.66 +/- 34.26 HV) and the minimum specific wear rate (0.12 x 10-2 mm3/N. m) is attained in YC sample. High-temperature oxidation study at 1000 degrees C at 10 h also illustrates minimum weight change and maximum oxidation resistance in YT samples attributed to the lowest porosity. The present study cites the suitability of ceramic oxides for high-temperature sustainability.