(Dr. David McDowell, advisor)
"Simulations and Experimental Studies of Transformation Surfaces of Cuznal and Niti"
Shape memory alloys (SMAs) have a mechanical behavior significantly different from that of typical metals. The observed behavior in compression may differ substantially in tension. Furthermore, SMA transformation behavior depends strongly on initial crystallographic texture. The aim is to better take account of these characteristics in finite element simulations.
The use of modern methods of scale transition has allowed very accurate simulations of the behavior of shape memory alloys under complex cyclic loading, which is difficult to explore experimentally. In this thesis we use these numerical simulations to determine different transformation surfaces as a function of the crystallographic texture or the type of alloy. Then, experiments are used to verify the validity of the results of the simulations. The ultimate aim is to obtain analytical representations of these surfaces and then, to implement them into a finite element code for large-scale structural analysis.