Magnetic and Electrochemical Properties of FeCoCrNiZr x High-Entropy Alloys

Abstract:

FeCoCrNiZr_x (x=0.5, 0.75, 1) high-entropy alloys with different Zr contents were prepared by vacuum arc melting. The effects of Zr content on the microstructure, magnetic properties, and electrochemical corrosion properties of the alloys were studied. X-ray diffraction, scanning electron microscope, vibration sample magnetometer, and electrochemical workstation were used to study the magnetic property and electrochemical corrosion ability of FeCoCrNiZr_x alloys. Results show that FeCoCrNiZr_x alloy has typical eutectic structure, consisting of face-centered cubic solid solution and C15 Laves phase. With the increase of Zr content, the hardness of the alloy increases at first and then decreases. However, according to the synthesized static hysteresis curves, FeCoCrNiZr_0.5 alloy shows a mixture characteristic of paramagnetism and ferromagnetism, FeCoCrNiZr_0.75 alloy has paramagnetic behavior, and FeCoCrNiZr₁ alloy has typical ferromagnetism. Meanwhile, the FeCoCrNiZr_x alloy undergoes activation-passivation transition in 3.5wt% NaCl solution. When the content of Zr is 0.75at%, the polarization resistance of the alloy has the maximum impedance capacitance radius, and the corrosion resistance of the passive film is the strongest.

Key words:corrosion resistance;hardness;high-entropy alloy;magnetic property;microstructure