|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Revealing Transformation and Deformation Mechanisms in Niti-based High Temperature Shape Memory Alloys through Microstructural Investigations
||Lee Casalena, Fan Yang, Daniel R Coughlin, Glen S Bigelow, Darrell J Gaydosh, Santo A Padula, Othmane Benafan, Ronald D Noebe, Peter M Anderson, Yunzhi Wang, Michael J Mills
|On-Site Speaker (Planned)
High temperature shape memory alloys such as NiTiHf and NiTiAu are of significant interest to the automotive and aerospace industries for potential light-weight solid-state actuator applications. However, a thorough understanding of the complex microstructural mechanisms occurring is needed to maximize their transformation temperatures and work output, while minimizing the detrimental cyclic instability leading to functional fatigue. NiTiHf can be tailored to achieve a favorable balance of properties, including high strength, stability, and work output at temperatures approaching 300°C. Constant-force thermal cycling (CFTC) experiments performed on NiTiAu have demonstrated remarkable compositionally insensitive work output above 400°C. The behavior in both systems is strongly influenced by the formation of secondary phases. Advanced scanning transmission electron microscopy (STEM) based characterization techniques are being used to explore and understand the unusual behavior seen in these alloy systems.
||Planned: Supplemental Proceedings volume