A novel quantitative analysis approach for hole surface damage of ceramic matrix composites machined by abrasive waterjet

Abstract

To realize low-damage hole-making machining of AWJ-machined CMC, it is necessary to achieve quantitative analysis of hole surface damage. Therefore, a novel approach to quantifying damage based on the principle of invariance of damage area is proposed in this study. The amount of total damage is attributed to the sum of the equivalent average damage lengths of the four common types of damage (peripheral compound damage, tearing damage, crack damage, and burrs damage), which are uniformly arranged inside and outside the hole in sequence according to the principle of constant area. The influence law and influence mechanism of common process parameters on the surface damage in Cf/SiC during hole making via AWJ are investigated based on the established quantitative damage analysis model. The total surface damage increases with the increase of the standoff distance, and decreases with the increase of waterjet pressure and abrasive flow rate. The most significant factor affecting the total surface damage is the standoff distance, followed by waterjet pressure and abrasive flow rate. However, the effect of traverse speed is not noteworthy. The approach of quantitative damage analysis will provide the necessary theoretical basis and technical guidance for achieving low damage hole-making surface utilizing AWJ.