Effect of wire speed on subsurface cracks in wire sawing process of single crystal silicon carbide

The effect of wire speed on dynamic stress intensity factors (DSIFs) at subsurface crack tips in the wire sawing process of single crystal silicon carbide (SiC) is investigated. The analysis of wire speed is converted to dynamic excitation loads due to moving diamond abrasives on wire saw. The excitation loads are obtained from stress field around the abrasives considering the morphology of abrasives and scratching depth. The governing equations are established for the hexagonal crystal structures of SiC, and solutions under the dynamic excitation load are calculated using Laplace transformation and Fourier transformation. Results show that the scratching angle and length of cracks have a great influence on the DSIFs. However, the effect of wire speed on the ratio of maximum DSIFs and maximum static stress intensity factors (SSIFs) is relatively small when the wire speed is less than 100 m/s. This indicates that the wire sawing process can be simplified as a quasi-static process when analyzing subsurface cracks problem.