| Abstract Scope |
Martensitic transformation (MT) is a fundamental carrier of both elastic (reversible) and plastic (irreversible) strains and can offer many novel physical, mechanical and functional properties that conventional elasticity and plasticity carriers cannot, including superelasticity, shape memory effect, Invar and Elinvar anomalies, TRIP effect and excellent work-hardening capacity. However, the strain release by a MT is usually highly nonlinear, taking place in an avalanche fashion within a narrow temperature or stress range, which is difficult to control. In this presentation, we give an overview on recent efforts devoted to regulating and utilizing MTs in metastable beta-Ti alloys for controlled strain release under an applied load. In particular, we discuss several means that have been proven effective to turn the sharp, strongly first-order MT into a broadly smeared, apparently continuous transformation, including spatial variation of beta-phase stability induced by concentration modulation, nano shuffle-domain regulated MT, and deformation twin boundary regulated MT. |