| About this Abstract |
| Meeting |
Materials Science & Technology 2020
|
| Symposium
|
Interfaces and Phase Transformations
|
| Presentation Title |
Microstructure and Mechanical Properties of Pre-aged Thermo-Mechanically Processed NiTiHf Shape Memory Alloy |
| Author(s) |
Faith Gantz, Nathan Ley, Jessica Rider, Jordyn Ward, Drew Forbes, Marcus Young |
| On-Site Speaker (Planned) |
Faith Gantz |
| Abstract Scope |
Shape memory alloys (SMAs) are multifunctional materials with high energy density, providing a high power-to-weight ratio as actuators in various applications. NiTiHf presents a cost-effective solution for high temperature SMA actuators, i.e. those that exhibit transformation temperatures above ~115 °C. In this study, a Ni50.3Ti29.7Hf20 (at.%) HTSMA was industrially produced then hot-extruded. Some samples were hot-rolled to 25% reduction in thickness, then a portion of the extruded and hot rolled samples were subjected to conventional aging (3hrs between 450 and 750 °C), while the other portion was subjected to pre-aging (12hr at 300 °C) plus conventional aging. The processing and aging treatments were designed to control the H-phase precipitate nucleation and growth and to determine the coherency between the matrix and the nano-precipitate H-phase interface, respectively. The alloy maintained stable phase transformation properties between pre-aged and conventional aging treatments for the extruded and hot-rolled conditions. |