|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||O-35: The Effect of Ni Ion Implantation on the Nanoindentation Response of a Ni 50.5at%-Ti 49.5at% Shape Memory Alloy
||Daniel Hong, Alejandro Hinojos, Nan Li, Khalid Hattar, Jeremy E. Schaffer, Taiwu Yu, Yunzhi Wang, Michael Mills, Peter Anderson
|On-Site Speaker (Planned)
Ion implantation is explored as a novel method to control the superelastic response of a solution-treated Ni50.5-Ti49.5 shape memory alloy, through the creation of irradiation-defects that could serve as nucleation and/or pinning sites for a B2-B19’ phase transformation. Ni ion implantation, at dpa levels typically less than those reported for amorphization, is followed by nanoindentation into a polished cross-sectional surface. A nearly 70% increase in hardness is observed ~3 microns below the implanted surface, while maintaining comparable recoverable displacement. Upon reindentation into existing indents, a more linearized loading/unloading response with reduced hysteresis is observed compared to unimplanted material. The results suggest that Ni ion implantation is a novel avenue to process NiTi shape memory alloys. This work is supported by: the Department of Energy, Basic Energy Sciences (DE-SC0001258) and the Center for Integrated Nanotechnologies (2019BC0126) and The Ohio Supercomputer Center (PAS0676).
||Phase Transformations, Other,