High throughput determination of diffusion coefficients and hardness using diffusion couple technique of γ-phase Fe-Ni-Cu alloys at 1000 °C

Abstract

A high-throughput method was employed for γ-phase Fe-Ni-Cu alloy system. In this study solute and intrinsic diffusivities are determined from interdiffusion coefficients, alongside determining nano-indent hardness from diffusion couple experiments. This could be an important study to obtain various diffusivities and hardness-composition relationship with minimum experiments. Analysis of inter and intrinsic diffusion coefficients, along with thermodynamic factors, revealed significant diffusional interactions among the alloy elements. In addition, it has been shown that Cu is the slowest diffusing species, and the solute diffusivities alone cannot be used as criterion for determining the kinetics of alloying elements. The diffusion interactions in inter and intrinsic diffusion need not to be similar but interdiffusion coefficients are more convenient in practical uses. A high-throughput hardness-composition relations were developed, which illustrate the applicability of diffusion couples to enable high throughput determination of various properties as functions of compositions.