Densification Behavior of Mechanically Alloyed NiAl Powder Compact during Spark-plasma Sintering and its Mechanical Property

Abstract

Mechanically-alloyed NiAl powder was sintered by Spark-Plasma Sintering (SPS) process. Densification and behavior mechanical property were determined from the experimental results and analysis such as changes in linear shrinkage, shrinkage rate, microstructure, and phase during sintering process, Vickers hardness, and transverse-rupture-strength (TRS). Above 97% relative density was obtained after sintering at 1150℃ for 5 min. Crystallite size determined by the Scherrer method was approximately 80 nm. From the X-ray diffraction analysis it was confirmed that the sintered bodies were composed mainly of NiAl phase together with Ni3Al phase. Measured Vickers hardness and TRS value were 555±10 Hv and 1393±75 MPa , respectively.