Thermodynamics and kinetics of the Mg 65 Cu 25 Y 10 bulk metallic glass forming liquid

The thermodynamics and kinetics of the bulk metallic glass forming Mg65Cu25Y10 liquid were investigated using differential scanning calorimetry and three-point beam bending. The experiments lead to the determination of the thermodynamic functions as well as the viscosity of the supercooled liquid. The viscosity shows a temperature dependence, which is consistent with that of a strong glass similar to Zr–Ti–Cu–Ni–Be bulk metallic glasses or sodium silicate glasses. This contrasts with more fragile conventional metallic glass formers or pure metals. The relatively weak temperature dependence of the thermodynamic functions of the supercooled liquid is related to these sluggish kinetics in the supercooled liquid. Entropy, viscosity, and kinetic glass transition are compared in the frameworks of the fragility concept and the Adam–Gibbs theory. Strong liquid behavior retards the formation of crystals kinetically and thermodynamically.

[1]  W. Johnson,et al.  On the Glass Forming Ability of Bulk Metallic Glasses , 1996 .

[2]  C. Michaelsen,et al.  INVERSE MELTING OF METASTABLE NB-CR SOLID SOLUTIONS , 1996 .

[3]  W. Johnson,et al.  Strong Liquid Behavior of Zr-Ti-Cu-Ni-Be Bulk Metallic Glass Forming Alloys , 1996 .

[4]  Johnson,et al.  Atomic diffusion in the supercooled liquid and glassy states of the Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy. , 1995, Physical Review Letters.

[5]  W. Johnson,et al.  Hemispherical total emissivity and specific heat capacity of deeply undercooled Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 melts , 1995 .

[6]  W. Johnson,et al.  Thermodynamics and kinetics of the undercooled liquid and the glass transition of the Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 alloy , 1995 .

[7]  C. Angell,et al.  Formation of Glasses from Liquids and Biopolymers , 1995, Science.

[8]  W. Johnson,et al.  A highly processable metallic glass: Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 , 1993 .

[9]  Yan,et al.  Inverse melting in the Ti-Cr system. , 1993, Physical review. B, Condensed matter.

[10]  C. Angell.  Relaxation in liquids, polymers and plastic crystals — strong/fragile patterns and problems☆ , 1991 .

[11]  A. Inoue,et al.  Amorphous Zr–Al–TM (TM=Co, Ni, Cu) Alloys with Significant Supercooled Liquid Region of Over 100 K , 1991 .

[12]  A. Inoue,et al.  Mg–Cu–Y Amorphous Alloys with High Mechanical Strengths Produced by a Metallic Mold Casting Method , 1991 .

[13]  A. Inoue,et al.  Production of Amorphous Cylinder and Sheet of La55Al25Ni20 Alloy by a Metallic Mold Casting Method , 1990 .

[14]  G. Adam,et al.  On the Temperature Dependence of Cooperative Relaxation Properties in Glass‐Forming Liquids , 1965 .

[15]  H. E. Hagy,et al.  Experimental Evaluation of Beam‐Bending Method of Determining Glass Viscosities in the Range 108 to 1015 Poises , 1963 .

[16]  W. Kauzmann.  The Nature of the Glassy State and the Behavior of Liquids at Low Temperatures. , 1948 .