Investigation of Phase Composition and Microstructure of the FeAl/Al<sub>2</sub>O<sub>3</sub> Composites Fabricated by Mechanical Alloying and Hot-Pressing Process

Abstract

The FeAl/Al2O3composites were fabricated by hot-pressing process in this research. The Fe-Al intermetallics compounds powders were fabricated by mechanical alloying and heat treatment. The FeAl powders and Al2O3powders were mixed and the FeAl/Al2O3composite powders were prepared. The FeAl/Al2O3composites bulks were fabricated by hot-pressing process at 1300°C for 2h under the pressure of 35MPa. The phase composition and microstructure of the FeAl intermetallics compounds powders produced by mechanical alloying and heat treatment were investigated. The phase composition and microstructure of the FeAl/Al2O3composites produced by hot-pressing process were investigated. The XRD patterns results showed that the Fe-Al intermetallics compounds powders were fabricated by mechanical alloying for 60h. The FeAl intermetallics compounds powders were fabricated by heat treatment at 800°C, 900°C and 1000°C. The microstructure showed that the mean particles size of the FeAl intermetallics compounds powders produced by mechanical alloying and heat treatment was rather fine and about 4-5μm. The XRD patterns results showed that there existed FeAl phase and Al2O3phase in sintered composites. The FeAl/Al2O3composites bulks exhibited the homogenous and compact microstructure. The mean particles size of FeAl was about 4-5μm and the mean particles size of Al2O3was about 4-5μm. The microstructure of the FeAl/Al2O3composites became more homogenous and compact with the increase of FeAl content.