Towards a modeling of the time dependence of contact area between solid bodies

摘要: I present a simple model of the time dependence contact area between solid bodies, assuming either totally uncorrelated surface topography, or self affine roughness. The existence relaxation effects (that incorporate using recently proposed model) produces increase $A(t)$ towards an asymptotic value that can be much smaller than nominal area. For evolution is numerically found to well fitted by expressions form [$A(\infty)-A(t)]\sim (t+t_0)^{-q}$, where exponent $q$ depends on normal load $F_N$ as $q\sim F_N^{\beta}$, with $\beta$ close 0.5. In particular, when lower obtain $A(t)/A(0) \sim 1+C\ln(t/t_0+1)$, i.e., logarithmic area, in accordance experimental observations. for low loads also obtained analytically this case. more realistic case surfaces, results are qualitatively similar.