Compatibility at junction planes between habit plane variants with internal twin in Ti-Ni-Pd shape memory alloy

Abstract

The kinematic compatibility (KC) between habit plane variants (HPVs) was numerically analyzed and classified in Ti-25Ni-25Pd alloy. There are six distinct types of HPV pair that can satisfy the KC condition at averaged junction plane (JP) between twinned HPVs. By analyzing the KC condition between lattice correspondence variants (CVs) in the HPVs, it was found that there are three types of HPV pair in which all the CVs can be compatible due to the existence of the common rotation to keep the KC at all JPs simultaneously. On the other hand, it was found that the incompatibility inevitably remains in the morphologies known as spear (wedge), folk and herring-bone.