|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||High Entropy Alloys VIII
||J-55: Origin of High Cr Cation Fractions in Passive Oxide of Ni38Fe20CrxMn21-0.5xCo21-0.5x High Entropy Alloys
||Junsoo Han, Angela Gerard, Xuejie Li, James Saal, Pin Lu, Wolfgang Windl, Kevin Michael Ogle, Gerald Frankel, John R. Scully
|On-Site Speaker (Planned)
An important characteristic of the passive film of an alloy is which alloying elements are present in the oxide film and are responsible for the controlling passivity. Oxide enrichment models have been proposed derived from the relative dissolution rates of pure elements and the concentration of each element in the bulk alloy.
In this work, the evolution of oxide cation fraction in the passive film on a high entropy alloy (Ni-Cr-Fe-Mn-Co) in a 0.1 M NaCl solution was compared to other alloys at the same Cr content. Cr enrichment was determined using X-ray photoelectron spectroscopy (XPS). To track the elemental dissolution in real time, atomic emission spectroelectrochemistry (AESEC) was applied, which directly measures the dissolution rate of each element during electrochemical tests. The fate of each element was tracked. Non-congruent low Cr dissolution rate coupled with preferential dissolution of other elements will be discussed.
||Planned: Supplemental Proceedings volume; Planned: Supplemental Proceedings volume