|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Innovations in High Entropy Alloys and Bulk Metallic Glasses: An SMD & FMD Symposium in Honor of Peter K. Liaw
||Creep Resistance of a Hierarchical-precipitate-strengthened Ferritic Alloy
||Gian Song, Soon Jik Hong, Jin Kyu Lee, Sung Ho Song, Sung Hwan Hong, Ki Buem Kim, Yanfei Gao, Zhiqian Sun, Peter K. Liaw
|On-Site Speaker (Planned)
Hierarchical NiAl/Ni2TiAl-precipitate-strengthened ferritic alloys have been developed by adding Ti into a previously-studied NiAl-precipitate-strengthened ferritic alloy. A systematic investigation has been conducted to study the interrelationships among the composition, microstructure, and mechanical behavior, and provide insight into deformation micro-mechanisms at elevated temperatures. The microstructural attributes of hierarchical ferritic alloys contain a two-phase NiAl/Ni2TiAl precipitate, which is coherently distributed in the Fe matrix. The creep resistance is significantly improved than the NiAl-strengthened ferritic alloy without the Ti addition. The microstructural evolution of precipitates during heat treatment is investigated using transmission-electron microscopy and atom-probe tomography are used to study the precipitate evolution, such as the size, morphology, composition of the precipitates. It was found that the hierarchical structure within the precipitate evolves from the fine two-phase-coupled to agglomerated coarse structures, as the aging time increases. Moreover, transition from the coherency to semi-coherency is concomitant with that of hierarchical structure within the precipitate.
||Planned: Supplemental Proceedings volume