|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Mechanical Properties of NiMnGa Alloys as a Function of Composition and Phase Transformations Measured by Nanoindentation
||Le Zhou, Anit Giri, Kyu Cho, Yongho Sohn
|On-Site Speaker (Planned)
Elastic modulus and hardness for NiMnGa alloys were investigated using nanoindentation over a large compositional range generated from solid-to-solid diffusion couples. The microstructure and concentration profile were obtained by scanning electron microscopy and electron probe microanalysis, respectively. Compositions generated by diffusion couples covered a large portion of the β phase, and an interface separating austenite and martensite was created for each diffusion couple upon cooling to room temperature. Nanoindentation measurements for elastic modulus and hardness were carried out through the interdiffusion zone, including across the austenite/martensite interfaces for each diffusion couple. A minimum value of elastic modulus or hardness was always observed near the interface between austenite and martensite. Moreover, the scatter of elastic modulus and hardness for the martensite is generally much larger than for the austenite. Observations were analyzed with respect to compositions, orientation, shape memory effect and lattice softening of the NiMnGa alloys.
||Planned: A print-only volume