Thermodynamic prediction of bulk metallic glass forming alloys in ternary Zr–Cu–X (X = Ag, Al, Ti, Ga) systems

• Published in: Journal of non-crystalline solids 2011-10, Vol.357 (19), p.3495-3499
• Main Authors: Vincent, S., Peshwe, D.R., Murty, B.S., Bhatt, Jatin
• Format: Article
• Language: English
• Subjects: Alloys; Amorphous materials; AMORPHOUS STRUCTURE; Bulk metallic glasses; Configurational entropy; Cross-disciplinary physics: materials science; rheology; Enthalpy of chemical mixing; ENTROPY; Exact sciences and technology; FORMING; Gallium base alloys; GLASSES; Glasses (including metallic glasses); Materials science; Metallic glasses; Mismatch entropy; Physics; Specific materials; THERMODYNAMIC PROPERTIES; Thermodynamics; ZIRCONIUM ALLOYS (50 TO 99 ZR); Zirconium base alloys
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2011.06.024

Prediction of bulk metallic glass (BMG) forming compositions has always been a challenge due to thermodynamic and kinetic constraints. In the present investigation, a parameter based on the enthalpy of chemical mixing (∆ H chem) and the mismatch entropy (∆ S σ/ k B) has been used to correlate with glass forming ability in some Zr based BMGs. The new thermodynamic parameter, P HS = ∆ H chem × ∆ S σ/ k B, is found to have strong correlation with glass forming ability in the configurational entropy (∆ S config/ R) range of 0.9–1.0. P HS has been calculated for compositions in Zr–Cu–Ag, Zr–Cu–Al, Zr–Cu–Ti and Zr–Cu–Ga ternary systems. It is observed that in all the systems studied, the best BMG composition (highest critical diameter ( Z c) of glass formation) is the one that corresponds to the highest negative P HS value. Present approach using P HS could be road map to design new BMG forming compositions. ► Isometric contour using thermodynamic and topological parameters are judiciously used to design BMG forming composition. ► BMG forming compositions with the highest critical diameter are predicted using present model in Zr based ternary systems. ► Proposed new theoretical parameter, P HS, is found to have strong correlation with bulk metallic glass forming ability.