|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Effect of Wire Diameter on Phase and Kirkendall Pore Evolution in Titanium Coated Nickel Wires
||Dinc Erdeniz, Arun Bhattacharjee, Aaron Yost, David Dunand, Ashley Paz y Puente
|On-Site Speaker (Planned)
Because of their shape-memory and superelastic properties, near equiatomic nickel-titanium alloys (NiTi) have several applications, which can be further enhanced by having a porous structure. However, fabrication of such porous structures is challenging due to processing difficulties stemming from the high melting point and reactivity of NiTi. To overcome these issues, one potential approach is to decouple the fabrication and alloying of Ni scaffolds. As a precursor to producing the full scaffold structure, pure Ni wires with four different sizes (25, 50, 75, 100 μm) were coated with sufficient Ti via pack cementation such that, upon homogenization, they transform into near equiatomic NiTi. During coating and homogenization, interdiffusion results in the formation of Kirkendall pores, which eventually coalesce into a single central channel, converting the wires into micro-tubes. Both ex situ metallography and in situ X-ray tomography were used to study the effects of wire size on the microstructural evolution.
||Planned: Supplemental Proceedings volume