Cu-based bulk glassy alloys with high tensile strength of over 2000 MPa

• Published in: Journal of non-crystalline solids 2002-06, Vol.304 (1), p.200-209
• Main Authors: Inoue, Akihisa, Zhang, Wei, Zhang, Tao, Kurosaka, Kei
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Deformation and plasticity (including yield, ductility, and superplasticity); Exact sciences and technology; Mechanical and acoustical properties of condensed matter; Mechanical properties of solids; Physics
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/S0022-3093(02)01025-6

Cu-based glassy alloys with tensile strength of over 2000 MPa were synthesized in Cu–Zr–Ti and Cu–Hf–Ti ternary and Cu–Zr–Hf–Ti and Cu–Zr–Ti–Y quaternary systems by copper mold casting. The critical diameter was 4 mm for the Cu 60Zr 30Ti 10 and Cu 60Hf 25Ti 15 ternary alloys and the Cu 60Zr 20Hf 10Ti 10 and Cu 60Zr 10Hf 15Ti 15 quaternary alloys and 5 mm for the (Cu 0.6Zr 0.3Ti 0.1) 98Y 2 alloy. As the Ti content increases, the glass transition temperature ( T g), crystallization temperature ( T x) and temperature interval of supercooled liquid region, ΔT x(= T x− T g), decrease, while the liquidus temperature ( T l) has a minimum of 1127 K around 20% Ti, resulting in a maximum T g/ T l of 0.63 in the vicinity of 20% Ti. The bulk glass-forming ability was obtained at the compositions with T g/ T l>0.60. The glassy alloys have a fracture strengths between 2050 and 2160 MPa and plastic elongations of 0.8–1.7%. The finding of the Cu-based bulk glassy alloys with T g/ T l>0.60, fracture strength >2000 MPa and plastic elongation indicates a possibility for subsequent development of glassy alloys with new compositions which can be used for structural materials.