Strain perceptibility of elements on the diffusion in Zr-based amorphous alloys

Area of Science:

• Materials Science
• Solid State Physics
• Physical Chemistry

Background:

• Bulk metallic glasses (BMGs) exhibit unique mechanical properties.
• Understanding diffusion mechanisms in BMGs is crucial but remains largely unexplored.
• Deformation-induced structural changes significantly impact material behavior.

Purpose of the Study:

• To investigate the influence of deformation-induced structural transformations on diffusion in Zr-based BMGs.
• To differentiate diffusion mechanisms under various strain conditions (as-cast, stressed, deformed).
• To compare the applicability of the vacancy and transition state models.

Main Methods:

• Experimental investigation of diffusion processes and elemental distribution in BMGs.
• Application of plastic deformation via cold rolling and elastostatic cyclic compression.
• Analysis using vacancy and transition state diffusion models.

Main Results:

• Viscoelastic strain governs the transition-state model for tracer atom (Fe) diffusion.
• Plastic strain governs the vacancy model for constituent atom (Ti, Zr) diffusion.
• Diffusion behavior is tunable by altering constituent elements and strain modes.

Conclusions:

• Deformation significantly alters diffusion in bulk metallic glasses.
• Distinct diffusion mechanisms are operative for tracer and constituent atoms.
• Tailoring BMG composition and deformation methods can control diffusion properties.