DYNAMIC PHOTOELASTIC INVESTIGATION ON THE MECHANICS OF WATERJET AND ABRASIVE WATERJET MACHINING

An experimental investigation was conducted to study the mechanics of material removal in waterjet and abrasive waterjet (AWJ) piercing processes in a birefringent polymer material. A two-dimensional dynamic photoelasticity experimental set-up was developed and utilized to record the photoelastic stress patterns associated with jet piercing. The fringe patterns recorded by the high-speed camera were used to identify the transient stress fields adjacent to holes pierced. A comparative study of material-removal mechanisms with pure-waterjet and abrasive-waterjet impacting and piercing show that a waterjet contributes to the macrocracking and scooping action of that material, whereas an abrasive waterjet contributes to microcrack nucleation, micromachining, and subsequently erosion.