Effect of Al addition on properties of Cu45Zr45.5Ti9.5 bulk metallic glass

• Published in: Materials chemistry and physics Vol. 251; p. 123072
• Main Authors: Cai, A.H., Tan, Jing, Ding, D.W., Wang, Hui, Liu, Y., Wu, H., An, Q., Ning, H., Zhou, G.J.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01-09-2020; Elsevier BV
• Subjects: Al addition; Aluminum; Amorphous materials; Compression tests; Copper; Corrosion; Corrosion currents; Corrosion potential; Cu-based glass forming alloy; Fracture strength; Glass transition temperature; Hardening; Heterogeneity; Mechanical property; Metallic glasses; Microalloying; Pitting (corrosion); Properties (attributes); Room temperature; Thermal measurement; Thermal property; Thermal property; Cu-based glass forming alloy; Corrosion; Mechanical property; Al addition
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2020.123072

The thermal, mechanical and corrosive properties of (Cu45Zr45.5Ti9.5)100-xAlx (x = 0–0.25 at%) glass forming alloys were systematically studied. The thermal measurements show that Al microalloying leads to increase of glass transition temperature but decrease of supercooled liquid region. The glass transition activation energy slightly increases and then decreases with increasing Al content. The room-temperature compression tests demonstrate that all studied Cu-based bulk metallic glasses (BMGs) exhibit work-hardening behavior, but the work-hardening capacity depends on Al content. In addition, yield strength, fracture strength and fracture strain are drastically increased by Al addition. The largest plasticity of (Cu45Zr45.5Ti9.5)99.8Al0.2 BMG is 6 times larger than that of the Al-free Cu-based BMG. Moreover, the electrochemical measurements indicate that the Al minor addition cause the decrease of both corrosion potential and corrosion current density. The corrosion behavior gradually transforms from the pitting corrosion to the self-passivization with increasing Al content. The local heterogeneity of Al element is thought to be the reason for the performance change of the studied Cu-based BMGs. The present results would provide a new insight into the mechanism for the microalloying effect on the properties of the metallic glasses.
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•Supercooled liquid region is narrowed by Al microallying.•Mechanical properties are remarkably enhanced by Al microallying.•Both corrosion potential and corrosion current density decrease by Al microallying.