|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||High Entropy Alloys VI
||Diffusion in CoCrFeNi Based High Entropy Alloys
||Abhishek Mehta, Le Zhou, Esin Schulz, Yongho Sohn
|On-Site Speaker (Planned)
Interdiffusion and tracer diffusion coefficients in the CoCrFeNi high entropy alloys (HEAs) were simultaneously determined in the temperature range of 900º to 1200ºC by using solid-to-solid diffusion couples combined with sandwiched thin-film technique proposed by Belova et al. (Phil. Mag., 2015). Phase constituents, microstructure and concentration profiles were examined by X-ray diffraction and scanning electron microscopy with X-ray energy dispersive spectroscopy. Cr was observed to be the fastest and Ni was the slowest species of interdiffusion. Activation energy estimated from average effective interdiffusion coefficients ranged from 290 to 390 KJ/mole, depending on the elemental constituents and composition. Kirkendall pores spread over a large distance, e.g., ~100 micrometers, within the interdiffusion zone were observed. Interdiffusion and tracer diffusion coefficients determined were compared to reported values in relevant unary, binary, ternary and HEA systems. Findings from this study are discussed with thermodynamic and kinetic contribution in the design approach for HEAs.
||Planned: Supplemental Proceedings volume