Issue |
J. Phys. Colloques
Volume 43, Number C4, Décembre 1982
ICOMAT-82International Conference on Martensitic Transformations |
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Page(s) | C4-145 - C4-150 | |
DOI | https://doi.org/10.1051/jphyscol:1982415 |
International Conference on Martensitic Transformations
J. Phys. Colloques 43 (1982) C4-145-C4-150
DOI: 10.1051/jphyscol:1982415
STRUCTURAL PHASE TRANSFORMATIONS IN THE INDIUM-RICH SOLID SOLUTIONS
Y. Koyama et O. NittonoDepartment of Metallurgy, Faculty of Engineering, Tokyo Institute of Technology, Tokyo 152, Japan
Abstract
It is shown that there are four kinds of phase transformation in Indium-rich alloys containing solute atoms such as Cd, Hg, Tl, Sn and Pb as follows : (1) fcc [MATH] fct(c/a>1), (2) fcc [MATH] fct(c/a<1), (3) fct(c/a<1) [MATH] fco [MATH] fct (c/a>1) and (4) fct(c/a<1) [MATH] fct(c/a>1). The results obtained in these transformations are discussed m terms of the Landau theory based on the group theory. It is concluded that a responsible representation for these transformations is two-dimensional representation Eg belonging to the cubic point group Oh. The fcc [MATH] fct transformation in In-Tl, In-Cd, In-Hg and In-Pb alloys and the fact(c/a<1) [MATH] fco in In-Pb-Sn alloys are quantitatively analyzed in terms of the Gibbs free energy, which is expressed by two order parameters such as two spontaneous strains corresponding to the two-dimensional representation Eg. The effect of the electron-atom ratio and the atomic size on the transformation behaviour is also discussed.