Investigation of Fabrication and Microstructure of the Fe<sub>3</sub>Al/Al<sub>2</sub>O<sub>3</sub> Composites by Plasma Active Sintering Process

Abstract

The Fe3Al/Al2O3 composites were fabricated by plasma active sintering process. The Fe3Al intermetallics compounds powders were fabricated by mechanical alloying and heat treatment. The Fe3Al intermetallics compounds powders and Al2O3 powders were mixed together, so the Fe3Al/Al2O3 composites were fabricated by plasma active sintering process at 1200oC for 5min under the pressure of 30MPa. The phase composition and microstructure of the Fe3Al intermetallics compounds powders produced by mechanical alloying and heat treatment were investigated. The phase composition and microstructure of the Fe3Al/Al2O3 composites produced by plasma active sintering process were investigated. The XRD patterns results showed that the Fe3Al intermetallics compounds powders were fabricated by mechanical alloying for 60h and heat treatment process. The XRD patterns results showed that there existed Fe3Al phase and Al2O3 phase in sintered composites. The microstructure showed that the mean particles size of the Fe3Al intermetallics compounds powders produced by mechanical alloying and heat treatment was about 4-5μm. The Fe3Al/Al2O3 composites exhibited the homogenous and compact microstructure. The mean particles size of Fe3Al was about 2-3μm and mean particles size of Al2O3 was about 2-3μm. The Fe3Al/Al2O3 composites exhibited homogenous and compact microstructure with the increase of Fe3Al content. The density and relative density of the Fe3Al/Al2O3 composites increased gradually with the increase of Fe3Al content.