|About this Abstract
||Materials Science & Technology 2019
||Advanced Manufacturing, Processing, Characterization and Modeling of Functional Materials
||Synchrotron Radiation X-ray Diffraction Measurements on Non-metallic Inclusions and their Effect on Fatigue Life in NiTiHf High Temperature Shape Memory Alloys
||Nathan A. Ley, Choongyep Lee, Robert W. Wheeler, Dimitris C. Lagoudas, Marcus L. Young
|On-Site Speaker (Planned)
||Nathan A. Ley
High temperature shape memory alloys (HTSMAs) have many potential applications in the aerospace, automotive, and defense industries due to their ability to perform significant amounts of repeatable actuation work at elevated temperatures above 100 °C. While there has been initial early success with NiTiHf HTSMAs, several issues still exists that need to be resolved in order for NiTiHf to become a more viable alloy. One of the major issues is how different types of non-metallic inclusions (NMIs) formed during the melting and processing of the alloy affect the actuation fatigue life of NiTiHf. In this study, the actuation fatigue behavior of two different melts of NiTiHf were examined: one with apx. 1% and a second with less than 0.1% volume fraction of a (Ti,Hf)C phase. The material lots were characterized using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), thermo-mechanical fatigue testing, and synchrotron radiation x-ray diffraction (SR-XRD).