Glass-forming ability and properties of Hf-Cu-Ni-Al-Ag bulk metallic glasses

Abstract

Abstract A new Hf-based Hf-Cu-Ni-Al-Ag glassy alloy was synthesized to be formed by copper mold casting. The influence of Ag addition on the properties of Hf48Cu29.25Ni9.75Al13-xAgx (x=0-5at%) glassy alloys was studied by differential scanning calorimeter, X-ray diffractometer, quasi-static compression, and electrochemical corrosion test. The experimental results show that adding Ag can improve the thermal stability and glass-forming ability of glassy alloys. The Hf48Cu29.25Ni9.75Al12Ag1 exhibits the best glass-forming ability with a critical diameter of 12 mm and the highest compressive strength (2363 MPa) among glassy Hf48Cu29.25Ni9.75Al13-xAgx (x=0-5at%). The total plastic deformation of Hf48Cu29.25Ni9.75Al12Ag1 before fracture approaches 4%. In addition, there is a passivation interval of about 3 V for Hf48Cu29.25Ni9.75Al12Ag1 glassy alloy in 1 mol/L H2SO4 solution, which makes the passivation film more stable and increases the corrosion resistance. In 1 mol/L KOH solution, the corrosion tendency and rate decreased with the addition of Ag content, leading to increased corrosion resistance.