Determining the coefficient of friction between solids without sliding

A novel method for measuring the interfacial coefficient of friction between two solids which avoids sliding is described, and sample results are given. The technique makes use of the fact that a carefully controlled sequence of partial slip states between contacting bodies may be used to produce relative motion whose extent is a strong function of the coefficient of friction. It is argued that this approach induces much less surface damage in the components, and therefore yields a value for the coefficient of friction which is much more representative of their unmodified condition.