The emergence of small-scale self-affine surface roughness from deformation.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 32110722.
- Also identified by DOI 10.1126/sciadv.aax0847 and PMC identifier 7021500.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Most natural and man-made surfaces appear to be rough on many length scales. There is presently no unifying theory of the origin of roughness or the self-affine nature of surface topography. One likely contributor to the formation of roughness is deformation, which underlies many processes that shape surfaces such as machining, fracture, and wear. Using molecular dynamics, we simulate the biaxial compression of single-crystal Au, the high-entropy alloy Ni<sub>36.67</sub>Co<sub>30</sub>Fe<sub>16.67</sub>Ti<sub>16.67</sub>, and amorphous Cu<sub>50</sub>Zr<sub>50</sub> and show that even surfaces of homogeneous materials develop a self-affine structure. By characterizing subsurface deformation, we connect the self-affinity of the surface to the spatial correlation of deformation events occurring within the bulk and present scaling relations for the evolution of roughness with strain. These results open routes toward interpreting and engineering roughness profiles.