English

Self-affine surface morphology of plastically deformed metals

Statistical Mechanics 2009-11-10 v1 Materials Science

Abstract

We analyze the surface morphology of metals after plastic deformation over a range of scales from 10 nm to 2 mm, using a combination of atomic force microscopy and scanning white-light interferometry. We demonstrate that an initially smooth surface during deformation develops self-affine roughness over almost four orders of magnitude in scale. The Hurst exponent HH of one-dimensional surface profiles is initially found to decrease with increasing strain and then stabilizes at H0.75H \approx 0.75. By analyzing their statistical properties we show that the one-dimensional surface profiles can be mathematically modelled as graphs of a fractional Brownian motion. Our findings can be understood in terms of a fractal distribution of plastic strain within the deformed samples.

Keywords

Cite

@article{arxiv.cond-mat/0405069,
  title  = {Self-affine surface morphology of plastically deformed metals},
  author = {Michael Zaiser and Frederic Maqdani and Vasileios Koutsos and Elias Aifantis},
  journal= {arXiv preprint arXiv:cond-mat/0405069},
  year   = {2009}
}