Minimisation of kerf tapers in abrasive waterjet machining of alumina ceramics using a compensation technique

Abstract

Kerf taper is a special and undesirable geometrical feature inherent to abrasive waterjet (AWJ) machining. In this study, an experimental investigation is carried out to minimise or eliminate the kerf taper in AWJ cutting of alumina ceramics by using a kerf-taper compensation technique. Among the cutting parameters studied, kerf-taper compensation angle is found to have the most significant effect on the kerf taper and the kerf taper angle varies almost linearly with this compensation angle. It shows that with this technique, it is possible to achieve a zero kerf taper angle without compromising the nozzle traverse speed or cutting rate. Depending on the other cutting parameters considered in this study, it is found that a kerf-taper compensation angle in the range of 4–5° can minimise the kerf taper angle to around zero. Using a dimensional analysis technique, a predictive model for the kerf taper angle is then developed and verified. An assessment of the model shows that the model can give adequate predictions with an average percentage deviation of 6.2% and the standard deviation of 13.4% from the corresponding experimental data.