Cu-Al-Ni microstructure in the phenomenological theory of martensite with lattice invariant deformation

Abstract

Abstract. Geometrical analysis of interfaces in a Cu-Al-Ni alloy is performed on the basis of the phenomenological theory of martensite. The austenite-martensite interfaces in the foils of the Cu-Al-Ni alloy are faceted. In order to assess possible facet planes, lattice invariant deformation in the form of a simple shear is included into the phenomenological theory. The experimentally observed normals to the facet planes lie in the predicted regions. Experimentally observed lines in the intervariant interfaces are interpreted as slip steps. The directions of these lines agree with theoretical predictions.

In-situTEM study of stress-induced transformations in CuAlNi

“…The nature of the simple shear is being examined at present. However, preliminary results [25] indicate that it might be related to the structural defects observed in 1 martensite (Fig. 4).…”

“…As described in [23] the habit plane crystallography depicted in Fig. 3 can be no more explained in the frame of 2-dimensional (thin film) phenomenological theory and must be treated as a 3-dimentional case [24,25] could be detected in the vicinity of the {331} 1 segments, a simple shear was taken as a lattice-invariant deformation in the model. The nature of the simple shear is being examined at present.…”