Interfacial dislocations in frictional sliding and interfacial creep

Abstract

The hypothesis is put forward that there may be circumstances in which frictional sliding occurs by the movement of elastic, non-crystalline dislocations in the sliding interface. The three main types of these interfacial dislocations (interfaceons) are described. An equation for the friction-coefficient (μi) is derived for the sliding at velocity s of a model visco-elastic material. Here Λ₂ and Λ₁ are relaxation-times for the material (a simple linear solid), b is a displacement-vector analogous to Burgers vector, [sgrave]N is the normal stress and Y the elastic modulus. Experimental data are examined which, it is shown, confirm that the hypothetical process does indeed occur in certain types of rubber, where it can account for the whole of the sliding.