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arXiv · 0805.0712

On the elastic energy and stress correlation in the contact between elastic solids with randomly rough surfaces

B. N. J. Persson
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Abstract

When two elastic solids with randomly rough surfaces are brought in contact, a very inhomogeneous stress distribution sigma(x) will occur at the interface. Here I study the elastic energy and the correlation function , where sigma(q) is the Fourier transform of sigma(x) and where <...> stands for ensemble average. I relate to the elastic energy stored at the interface, and I show that for self affine fractal surfaces, quite generally \sim q^{-(1+H)}, where H is the Hurst exponent of the self-affine fractal surface.

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B. N. J. Persson. 2008-05-06. On the elastic energy and stress correlation in the contact between elastic solids with randomly rough surfaces. https://doi.org/10.1088/0953-8984%2F20%2F31%2F312001

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