Microstructural characterization and enhanced hardness of nanostructured Ni3Ti-NiTi (B2) intermetallic alloy produced by mechanical alloying and fast microwave-assisted sintering process

Abstract

In this paper, the rapid synthesis of nanostructured NiTi-Ni3Ti intermetallic alloy from titanium and nickel powders through mechanical alloying followed by microwave-assisted sintering process was investigated. The sintered samples at different temperatures exhibited major phases of NiTi-B-2 and Ni3Ti, and minor phases of NiTi-B19' and Ti2Ni. The density, porosity and microhardness of the sample varied based on the sintering temperature, in which the highest density and microhardness (similar to 750 H V) were obtained at sintering temperature of 1100 degrees C. Based on the results of this research, the microwave-assisted sintering can be applied to fabricate Ni-Ti alloys with improved mechanical properties for biomedical applications.