Influence of Cr on Microstructure and Electrochemical Properties of FeNiMnCuCr_x High-entropy Alloy

The effects of Cr content on the variation of phase structure, microstructure and electrochemical properties of FeNiMnCuCr_x high-entropy alloys were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and electrochemical testing. The results showed that the alloys were FCC phase; the phase structure turned from single set of FCC to double sets of FCC with the increase of Cr. The microstructure transformed from columnar dendrites to equiaxed dendrites when the Cr content increased, and the microstructure refined. With the addition of Cr, the free corrosion current density showed the tendency of increasing first and decreasing afterwards. When x was equal to 1, the corrosion current density showed the lowest value of 7.8167×10^-7 A/cm².