In the micro-machining process, due to the cutting action of the cutting edge, the cutting edge is deformed in front of the crystal lattice of the workpiece material, as stored in the deformation of the lattice deformation can be accumulated to a certain extent, rearrange atoms begin to release stored in the lattice deformation energy. But the deformation energy stored is not enough to make all the atoms are rearranged, with the cutting edge of forward travel on the surface of the workpiece near the tool and the workpiece contact produced a crystal lattice dislocations, dislocation slip along different showing the direction of a discontinuous alternating motion, closely related to the fluctuation of the states and cutting forces generated. When the slip plane of the dislocation moves, some atoms with other atoms have a chance at a distance close to the range of a few atoms in size, then you can see some of the atoms move slightly between dislocations occurred, this process is continued during lattice vibration completed. Dislocations in zigzag shown in Fig. 3 toward macroscopic shear zone, and reaches the free surface by a shear zone, so that the chip size of an atomic layer is formed. From the generation and disappearance of lattice dislocations, the chips are like knives smoothly remove the same, and the dislocation lattice penetrate the workpiece the cutting edge of the inner surface of the bottom