Structural relaxation in a bulk metallic glass

• Published in: Journal of non-crystalline solids Vol. 325; no. 1; pp. 179 - 186
• Main Authors: Hammond, Vincent H., Houtz, Marlene D., O’Reilly, James M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.09.2003; Elsevier
• Subjects: Condensed matter: structure, mechanical and thermal properties; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; Glass transitions; Physics; Specific phase transitions; M190; S430; D190; Cooling rate; Experimental study; Structure relaxation; Glass formation; Fragility parameter; Multi-element alloys; Glass transition; Metallic glasses; DSC; Thermodynamic properties; Activation energy; Zirconium base alloys; Transition element alloys
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/S0022-3093(03)00311-9

Differential scanning calorimetry has been used to investigate the structural relaxation in a bulk metallic glass designated Vit 4. Results indicate that Vit 4 has a broad glass transition region with a glass transition temperature of approximately 621 K and an activation enthalpy of 834 kJ/mol. Despite the broad transition region, Wunderlich’s model suggests that structural relaxation in Vit 4 involves the cooperative motion of a single bead. The relaxation behavior was well described by the Tool–Narayanaswamy equation, with x and β values not significantly different from other glass formers. The dynamic and thermodynamic fragility of Vit 4 is compared with other glasses.