Abstract
The crystallography of B 2 - ζ2′ (trigonal) stress-induced transformation in Au-Cd has been controversial. The present study was undertaken to clarify this issue by obtaining reliable experimental data, which enabled a critical test for the phenomenological crystallographic theory of martensitic transformation. The results revealed that the lattice invariant shear (LIS) was {1 0 0}〈0 1 1〉C twinning in contrast to {0 1 1}〈1 0 0〉C twinning, which was believed to be the case by all the previous investigators. The theoretical calculations using {1 0 0}〈0 1 1〉C twinning agreed well with the observations in all respects. Therefore, the phenomenological crystallographic theory is shown to be well applicable to the present transformation. In addition to the stress-induced transformation, the morphologies of thermally induced martensites were examined, and two types of morphologies were observed: "roof-type" with LIS, and "herringbone-type" without LIS. Therefore, it is shown that transformations both with and without LIS are possible in the present transformation, and the previous discrepancy in LIS is rationalized.
Original language | English |
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Pages (from-to) | 3203-3211 |
Number of pages | 9 |
Journal | Acta Materialia |
Volume | 55 |
Issue number | 9 |
DOIs | |
Publication status | Published - May 2007 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Polymers and Plastics
- Metals and Alloys