JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, cilt.153, ss.164-169, 2004 (SCI-Expanded)
The behaviour of shape memory alloys, which exhibit a peculiar property, is evaluated by the structural changes in microscopic scale. Metastable beta phases of copper-based ternary alloys are very sensitive to the heat treatments and transform martensitically from the ordered structures to the long-period layered structures on cooling. Martensitic transformations in these alloys occur by two or more lattice invariant shears on a (001)(beta) plane of austenite matrix, which is basal plane or stacking plane of martensite. The basal plane of 9R (or 18R) type martensites originates from one of the (110)(beta) planes of the parent phase, and an homogenous shear occurs on the basal plane in either of two opposite directions during the transformation.