Abstract
Base on the real-time observation of the workpiece surface in a series of compression-sliding experiment, it is found that the contact area is much greater than that evaluated by the existing theorems such as the junction-growth theorem. With the aid of finite element analysis, it is verified that the tool sliding motion along with the minute elastic deformation of tool surface around the asperity peaks increase the asperity contact area significantly as the sliding motion continues. The existence of shear stress on the asperity peak also encourages the growth of contact area. An incremental model has been developed to predict the evolution of contact area with the relative sliding distance between tool and workpiece. The effect of the tool deformation on the variation of contact area is a function of the tool Young's modulus, the shear strength of workpiece, the current contact area, and the mean interface pressure.
