Effect of cooling rate during solidification on structure and mechanical properties of Cu45Zr48Al7 glass-forming alloy

• Published in: Journal of materials science Vol. 58; no. 41; pp. 16225 - 16238
• Main Authors: Kozieł, Tomasz, Cios, Grzegorz, Rutkowski, Bogdan, Wierzbicka-Miernik, Anna, Pajor, Krzysztof, Bała, Piotr
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.11.2023; Springer Nature B.V
• Subjects: Alloys; Amorphous alloys; Amorphous materials; Bulk sampling; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Cooling; Cooling effects; Cooling rate; Crystallization; Crystallography and Scattering Methods; Fracture strength; Glass; Glass formation; Glass matrix composites; Intermetallic phases; Materials Science; Mechanical properties; Metallic glasses; Metals & Corrosion; Plastic deformation; Polymer Sciences; Solid Mechanics; Solidification; Strain hardening; Zirconium
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-023-09024-y

The CuZr-based bulk metallic glass matrix composites have attracted great attention in recent years owing to their unique mechanical properties compared to bulk glassy samples. The vital effect of B2 CuZr phase on mechanical properties was previously confirmed in CuZr-based alloys with equiatomic concentrations of copper and zirconium. In this paper, the structures and mechanical properties of the Cu 45 Zr 48 Al 7 alloy, which has hypereutectoid composition with respect to stoichiometric B2 CuZr phase, were studied. This alloy exhibits high glass-forming ability, but low tendency to form the B2 CuZr phase during solidification. However, we demonstrated that depending on the cooling rate during solidification, governed by sample diameter, either bulk metallic glass or bulk metallic glass matrix composite can be produced. In order to allow partial crystallization of the B2 phase during solidification with the volume fraction allowing to observe the strain hardening effect, the minimum cooling rate should be lower than 40 K/s. The composite consisting of a glassy outer layer and a crystalline core composed of the B2 phase exhibits fracture strength of the same level as the bulk glassy sample (above 1800 MPa) obvious work-hardening with a plastic deformation of about 6%.