New (33) long-period microtwin variant in the martensitic phase of the PtTi alloy

The martensitic phase in the PtTi near-equiatomic alloy was extensively studied by electron microscopy techniques. A new 33 long-period stacking based on the expected B19 structure was observed as well as twinning on (1 1 1) planes. Based on electron diffraction and high-resolution imaging and the B2 to B19 transformation mechanism a new model was proposed and the agreement with experiments was checked by simulation of electron diffraction patterns and high-resolution images.