Effect of Cr/Mo content on the properties of transition-metal based high entropy bulk metallic glasses

In this work, new Fe ₂₀Co ₂₀Ni ₂₀Cr _xMo _20-xP ₁₀B ₁₀ ( x = 5, 10 and 15 at.%) high-entropy bulk metallic glasses (HE-BMGs) with the maximum diameter of 1.0–2.0 mm were prepared by combining fluxing treatment and J-quenching technique, and the effects of Cr/Mo content on thermal stability, mechanical properties, corrosion and wear resistances were systematically investigated. It is found that the glass transition temperature ( T _g) and onset crystallization temperature ( T _x) of the present transition-metal based HE-BMGs slightly decrease with the increase/decrease of Cr/Mo content. Compressive test shows that the compressive strength of the present transition-metal based HE-BMGs monotonously decrease from 3124 MPa for x = 5 to 2745 MPa for x = 15, but the compressive plasticity is nearly zero. Electrochemical measurements in 3.5 wt.% NaCl solution show that the corrosion resistance of the present transition-metal based HE-BMGs decrease with the increase/decrease of Cr/Mo content and the alloy with x = 15 exhibit the highest corrosion resistance with a self-corrosion current density of 1.02 × 10 ⁻⁸ A/cm ² among the present transition-metal based HE-BMGs. Wear test shows that, as the Cr/Mo content increases/decrease, the friction coefficient and wear rate of the present transition-based HE-BMGs decrease, i.e., wear resistance increases.