Hole characteristics and surface damage formation mechanisms of Cf/SiC composites machined by abrasive waterjet

Abrasive waterjet (AWJ) has a significant impact on the dimensional accuracy and machining damage of C-f/SiC composites. Thus, this paper aims to investigate the hole characteristics and formation mechanisms of surface damages (e.g. crack damage, tearing damage, delamination damage and burr damage). The results show that the diameters of hole entrance and hole exit varies with the traverse speed, jet pressure, standoff distance, and abrasive flow rate within certain parameters range. The over-machined phenomenon has the greatest impact on the hole dimensional accuracy, which can be effectively enhanced by improving the jet trajectory. The formation mechanisms of various damages are also obtained. These results will guide realizing high-precision and low-damage hole machining for ceramic matrix composite material.