Thermomechanical Behavior of Shape-Memory Single Crystals and Polycrystals

9625304 Weng This project is to study the thermomechanical behavior in both single crystal and polycrystalline versions of shape-memory alloys (SMA). To make best use of these materials it is important that their behavior be modeled with precision. Thus constitutive equations that capture the phase transformations under thermal/mechanical loading, must be used. The phase transformations are thermoelastic in nature and are therefore driven by the thermodynamic forces of the system which is inherently a two phase one. A combined theoretical/experimental program will consider the three dimensional martensite-plate morphology as well as the shear and dilatational components of the transformation strains. ***