기계적합금화시킨 TiNi 분말의 열처리조건에 따른 상변화 및 Al/TiNi소결체 내에서의 미세조직 특성 = Phase Changes of Mechanically Alloyed TiNi Powders by Heat-treatment and Microstructural Properties in the Al/TiNi Sintered Materials

다국어 초록 (Multilingual Abstract)

Microstructure and phase transformation of mechanically alloyed TiNi powders added to aluminium matrix for enhancing the damping properties were studied. Four compositions between 48.5 and 51.5 at% Ti intermetallic compounds were selected to control the fraction of martensite phase. Mechanically alloyed TiNi powders were heat-treated at vacuum of $10^{-6}$ torr for crystallization. Ball milled AI/TiNi composite powders were swaged at room temperature and rolled at 450 $^{\circ}C$. After mechanical alloying for 10 hours, Ti and Ni elements were alloyed completely and amorphous phase was formed. Amorphous phase was crystallized to martensite (Bl9') and austenite(B2) after heat treating for 1 hour at the temperature of 850 $^{\circ}C$, and TiNi$_3$, intermetallic compound was partially formed. Considerable amount of martensite phase was remained after swaging and rolling.