FEM Simulation of the Martensitic Tranformation in NiTi Alloys

FEM Simulation of the Martensitic Tranformation in NiTi Alloys

Phase-field modeling of martensitic microstructure in NiTi shape memory alloys

A phase-field model is developed to study the cubic to monoclinic martensitic phase transformation in nickel–titanium (NiTi) shape memory alloys. Three-dimensional phase-field simulations show the nucleation and growth of monoclinic B190 multivariants that form a polytwinned martensitic microstructure. Parametric studies demonstrate that mechanical constraints and crystallographic orientation g...

Hysteresis in NiTi alloys

Large changes in hysteresis are reported as a function of applied stress under thermal cycling experiments in NiTi single crystals. In the low Ni alloy the thermal hysteresis expanded with increasing stress while in the high Ni alloy the thermal hysteresis contracted with increasing stress. The results in both cases meet the limit obtained from Differential Scanning Calorimetry at zero stress. ...

Detwinning in NiTi Alloys

This work focuses on the stress-induced transformation in solutionized and overaged single-crystal NiTi alloys. The potential role of detwinning on the recoverable strains was investigated both theoretically and also with temperature-cycling experiments. The detwinning is the growth of one variant within a martensite in expense of the other. It is shown that the experimental recoverable strains...

Martensitic Transformation of NiTi and NiTi- TiC Composites