The elastic-plasticity mechanics are applied to analyze the friction between tool and chip. According to the slip-line field theory, a series of theoretical formula and the friction coefficient is derived between the tool and chip. So the cutting process can be investigated. Based on the Orthogonal Cutting Model and the Mohr's circle stress, the cutting mechanism of the cladding and the surface integrity of machining can be studied.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.