|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Mechanical Behavior of Nanostructured Materials
||Understanding, Controlling, and Creating Martensitic Phase Transformations in Nanostructured Polycrystals and Metamaterials
||Sam Reeve, Yang Wang, Karthik Guda Vishnu, Alejandro Strachan
|On-Site Speaker (Planned)
We recently demonstrated tuning of properties with martensitic phase transformations of shape memory materials via epitaxial integration of dissimilar materials to engineer the energy landscape that governs the phase transition. Here we extend this work with the objective of engineering novel properties in metallic alloys via energy landscape engineering. We used large-scale molecular dynamics (MD) to study core/shell nanowires consisting of NiAl (non-transforming B2 phase) and Ni63Al37 phase transformation materials. This choice is motivated by an analysis of the energy vs. lattice parameter of the combined metamaterial that indicates epitaxial integration would result in ultra-low stiffness metallic systems. Explicit MD simulations of mechanical deformation of the core/shell nanowires reveal a variety of interesting properties including ultra-low stiffness (~4 GPa) while maintaining strength. The simulations reveal nucleation and propagation of martensitic transformation in the metamaterials and show spatial coexistence of austenite and martensite phases can be stabilized, resulting in ultra-low stiffness.
||Planned: Supplemental Proceedings volume