New FeNiCrMo(P, C, B) high-entropy bulk metallic glasses with unusual thermal stability and corrosion resistance

Abstract

New Fe20–35Ni20Cr20–30Mo5–15(P0.6C0.2B0.2)20 bulk metallic glasses with excellent thermal stability, strength, and corrosion resistance have been developed through the high-entropy alloy design strategy. The high-entropy bulk metallic glasses (HE-BMGs) possess larger supercooled liquid regions of ∼69 K, higher crystallization onset temperatures of ∼852 K, larger undercoolings of ∼109 K, and more sluggish crystallization process upon heating than the conventional metallic glass benefited from the high mixing entropy effect. The HE-BMGs also exhibit ultrahigh strength of ∼3.4 GPa, Vickers hardness of ∼1107, and superior corrosion resistance in acids and NaCl solutions by formation of highly stable Cr- and Mo-enriched passive films. The new metal-metalloid HE-BMG system and exceptional properties give the alloys good promise for both scientific and engineering applications.