Enhancing mechanical properties and corrosion resistance of Zr-based bulk metallic glasses by Ta addition

Abstract

Zr-based bulk metallic glasses (BMGs) hold great promise as engineering materials, owing to their exceptional strength and remarkable corrosion resistance. However, in the ZrCuAlFe system, which exhibits limited glass-forming ability (GFA), enhancing corrosion resistance further is crucial to meet stringent industrial standards. This study focuses on the preparation of a series of Zr₆₅Cu₂₀Al_10-xFe₅Ta_x (x = 0–2.5 atomic percent) BMGs through arc melting. We systematically investigate how the incorporation of Ta influences the GFA, mechanical properties, and corrosion resistance of these as-cast alloys. Our findings reveal that a small amount of Ta addition can significantly enhance both the room-temperature plasticity and corrosion resistance of these alloys in a 3.5% NaCl solution. Specifically, compression tests suggest that when 1.5 atomic percent of Ta is added, the room-temperature plasticity of the alloy enhances from 1.13% in the as-cast state to 5.49%, while the fracture strength increases from 1264.2 MPa to 1511 MPa. Additionally, electrochemical tests demonstrate that the alloy with 1.5 atomic percent Ta addition displays the widest passivation range (0.604 V) and the lowest self-corrosion current density (1.16 × 10^–7 A·cm^-2). In conclusion, our results provide valuable theoretical insights into the effects of Ta addition on the mechanical properties and corrosion resistance of Zr-based BMGs, thereby offering guidance for their potential engineering applications.