Nonequilibrium plastic roughening of metallic glasses yields self-affine topographies with strain-rate and temperature-dependent scaling exponents

Abstract

We study nonequilibrium roughening during compressive plastic flow of initially flat Cu${}_{50}$Zr${}_{50}$ metallic glass using large-scale molecular dynamics simulations. Roughness emerges at atomically flat interfaces beyond the yield point of the glass. A self-affine rough topography is imprinted at yield and is reinforced during subsequent deformation. The imprinted topographies have Hurst exponents that decrease with increasing strain-rate and temperature. After yield, the root-mean-square roughness amplitude grows as the square-root of the applied strain with a prefactor that also drops with increasing strain-rate and temperature. Our calculations reveal the emergence of spatial power-law correlations from homogeneous samples during plastic flow with exponents that depend on the rate of deformation and the temperature. The results have implications for interpreting and engineering roughness profiles.

arXiv comment11 pages, 4 figures

References in corpus (25)

• Dynamics of Viscoplastic Deformation in Amorphous Solids
• On the nature of surface roughness with application to contact mechanics, sealing, rubber friction and adhesion
• Quantitative characterization of surface topography using spectral analysis
• When are rough surfaces sticky?
• The effect of surface roughness on the adhesion of elastic solids
• A random critical point separates brittle and ductile yielding transitions in amorphous materials
• Shear yielding of amorphous glassy solids: Effect of temperature and strain rate
• Driving rate dependence of avalanche statistics and shapes at the yielding transition
• Avalanches in Strained Amorphous Solids: Does Inertia Destroy Critical Behavior?
• Scaling exponents for fracture surfaces in homogenous glass and glassy ceramics
• Self-affine surface morphology of plastically deformed metals
• Avalanche Size Scaling in Sheared Three-Dimensional Amorphous Solid
• Linking energy loss in soft adhesion to surface roughness
• Shear bands as manifestation of a criticality in yielding amorphous solids
• Mechanical Yield in Amorphous Solids: a First-Order Phase Transition
• The universal emergence of self-affine roughness from deformation
• Size of Plastic Events in Strained Amorphous Solids at Finite Temperatures
• Brittle yielding of amorphous solids at finite shear rates
• Role of fluctuations in the yielding transition of two-dimensional glasses
• Correlations of non-affine displacements in metallic glasses through the yield transition
• Frozen capillary waves on glass surfaces: an AFM study
• Thermally activated flow in models of amorphous solids
• The yielding of amorphous solids at finite temperatures
• Criticality in sheared, disordered solids. I. Rate effects in stress and diffusion
• Roughness and scaling properties of oxide glass surfaces at the nanoscale