著者

平野 賢一 大内 権一郎

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.32, no.7, pp.613-618, 1968 (Released:2008-04-04)

参考文献数

28

被引用文献数

3 15

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Reaction-diffusion in the Ti-Ni system was investigated in the temperature range between 500° and 900°C, using diffusion couples of pure Ti and pure Ni.Above the eutectoid temperature of the β-Ti solid solution, the greater part of the diffusion zone consisted of β-Ti, while the Ni solid solution scarcely grew in it at the experimental temperatures.All of the three intermediate phases, TiNi3, TiNi, Ti2Ni, existing in the equilibrium phase diagram were observed in the diffusion zone at all the experimental temperatures. The apparent activation energies for the growth of TiNi3, TiNi, Ti2Ni phases are 16.1, 27.2 and 11.9 kcal/mol, respectively. It appears that such low activation energies are attributed to the excess vacancies in the intermediate phases of nonstoichiometric compositions.The composition range of the TiNi phase was determined from the concentration-penetration curves of the diffusion couples, and compared with the results of other workers. The composition range tends to decrease as temperature decreases, and at the Ni-rich side it is in good agreement with that obtained by Hume-Rothery et al. and Parr et al., but at the Ti-rich side it is displaced to the Ti-richer side.