Xiangyu Zhao, Ma Liqun, Yi Ding
Mar 1, 2011
Transactions of Nonferrous Metals Society of China
Mechanical alloying and subsequent annealing treatment were carried out to investigate the evolution of the microstructure and morphology of the TiH2-Ni system. The Ni(Ti) solid solution was formed in the initial milling process. When the milling time was 60 h, the alloy with uniform elemental distribution showed an amorphous structure containing a small amount of TiH2 nanocrystalline phase. The annealing treatment at 693 K contributed to a completion of amorphization for the alloy milled for 60 h. For the treatment at 1 073 K, a crystallization reaction for the amorphous phase occurred, leading to the formation of Ti2Ni, TiNi, and TiNi3 compounds by a short time treatment. Moreover, a separation of Ni-rich phases from the matrix and a phase transition among these three compounds occur by a long time treatment.