A scratching force model of diamond abrasive particles in wire sawing of single crystal SiC

The wire sawing process for single crystal SiC can be regarded as nano and micro scratching on the work-piece with diamond abrasives. The surface/subsurface quality of wafers is affected by the forces in scratching. In this paper, a theoretical force model for nano and micro scratching in wire sawing of single crystal SiC at arbitrary scratching angle is proposed. The geometrical shape of diamond abrasives is discussed and simplified. Then, a primary force model for the simplified abrasive is established considering the interfacial friction coefficient between the abrasive and work-piece. Indention size effect based on strain gradient plasticity theory and elastic recovery are included in this model. Finally, the influences of input variables on the theoretical force under the actual machined depth in wire sawing are discussed. The validity of this model is verified through nano and micro scratching tests in literatures, and the theoretical model matches well with the experimental results.