Influences of hydrostatic pressure during casting and Pd content on as-cast phase in Zr-Al-Ni-Cu-Pd bulk alloys
- Institute for Materials Research, Tohoku University Katahira 2-1-1, Sendai 980-8577 (Japan)
The influences of sample diameter (D), Pd content (x), and hydrostatic pressure (P) in a chamber during casting on the structure of as cast Zr{sub 65}Al{sub 7.5}Ni{sub 10}Cu{sub 17.5-x}Pd{sub x}(x=10,17.5 at.%) bulk alloys were investigated. Zr{sub 65}Al{sub 7.5}Ni{sub 10}Cu{sub 7.5}Pd{sub 10} and Zr{sub 65}Al{sub 7.5}Ni{sub 10}Pd{sub 17.5} alloys (D=3 mm) cast in a vacuum chamber (P{approx}4.0x10{sup -3} Pa) were mainly of the tetragonal-Zr{sub 2}Ni equilibrium phase and nanosize icosahedral primary phase, respectively, while the same alloys cast in inert argon gas at atmospheric pressure (P{approx}0.1 MPa) were of the single glassy phase. Due to the higher cooling rate obtained by decreasing the sample diameter (D=2 mm) even in the vacuum chamber, the Zr{sub 65}Al{sub 7.5}Ni{sub 10}Pd{sub 17.5} alloy was still of the icosahedral phase, while the Zr{sub 65}Al{sub 7.5}Ni{sub 10}Cu{sub 7.5}Pd{sub 10} alloy froze into a single glassy phase. These results indicate that the temperature- and time- transformation curves for the icosahedral and subsequent equilibrium phase formations in the alloy system shifts to a shorter time side with decreasing P, and the pressure sensitivity of the icosahedral phase formation increases with x.
- OSTI ID:
- 20634268
- Journal Information:
- Applied Physics Letters, Vol. 85, Issue 12; Other Information: DOI: 10.1063/1.1790028; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Devitrification of Zr-Ni-Al-Cu-Ti(Nb,Ta) glassy alloys
Crystallization of Zr2PdxCu1-x and Zr2NixCu1-x Metallic Glass