NiAl계 기계적 합금분말의 특성 및 소결합금체의 제진특성 = Characteristics of Mechanically Alloyed Ni-Al Power and Damping Properties of Sintered Alloys

다국어 초록 (Multilingual Abstract)

Ni-Al is shape memory alloy in high temperature and is used as high damping material(HIDMET). NiAl alloy powders were prepared by mechanical alloying method and bulk specimens were produced using hot isostatic pressing techniques(HIP). Transformation behavior was investigated by differential scanning calorimeter (DSC), XRD. Particle size distribution and microstructures of mechanically alloyed powders were studied using particle size analyzer and scanning electron microscope (SEM). After 10 hours milling, XRD peak broadening apeared at the alloyed powders with compositions of Ni-36at%Al to 40at%Al. The NiAl and Ni_3Al intermetallic compounds were formed after water quenching of solution-treated powders and bulk samples at 1200℃. It is considered to be caused by fast diffusion of atoms for the formation of stable β(NiAl) phase and Ni_3Al due to nano sized grains during quenching. Amounts of martensite phase increased as the heat treatment times increased in the Ni-Al alloy, which resulted in the increasing damping properties.