Compensation of Taper Angle in Abrasive Water Jet Machining

Abstract

Abrasive water jet machining is one of the recent non-traditional manufacturing tech- nologies. It employs mixture of high pressure water and abrasives to remove the ma- terial at high rate without distortion and microstructure changes. Flexibility of the process explores its potential for shape machining of brittle and ductile material like aluminium, ceramics and glasses. This thesis contains an extensive literature review on the investigations of the various aspects in AWJ machining. It shows that while considerable work has been carried out, very little reported research has been found on the AWJ contouring process. The e ects of process parameters on the major cutting performance measures in AWJ contouring have been comprehensively discussed. An e ect of inherent characteristics of water jet aring on straightness of the through cut has been studied. In this thesis an attempt has been made to establish the e ect of jet traverse speed on straightness of the cut and surface roughness through experiments for di erent materials like aluminum, Stainless steel, sand stone and marble. Quantitative taper angle analysis and qualitative roughness analysis for these materials have been presented in this paper. The traverse speed at which non through cut produced was also found out through the experiments. A detailed experimental investigation is presented in this thesis to study the var- ious cutting performance measures in AWJ straight and contour cutting of SS304 material over a wide range of process parameters. The e ects of process parameters on the major cutting performance measures in AWJ cutting have been comprehen- sively discussed and the trends are amply analyzed. It nds that the taper angles as well as surface roughness on the two kerf walls are in di erent magnitudes in AWJ contouring. The kerf taper on the outer kerf wall increases with the arc radius (or pro le curvature), while that on the inner kerf wall decreases. Moreover The other process variables a ect the AWJ contouring process in a way similar to that in straight cutting. The analysis has provided a guideline for the selection of process parameters in the AWJ straight and pro le cutting in order to predict the cutting performance in process planning and ultimately optimize the cutting process, mathematical models for both straight and contour cutting has been developed using a Response surface method. The models are then veri ed by assessing both qualitatively and quantitatively the model predictions with respect to the corresponding experimental data. It shows that the models can adequately predict the cutting performance measures and form the essential basis for developing strategies for selecting the optimum process parameters in AWJ cutting.