Integral modeling of abrasive waterjet micro-machining process

Abrasive water jet technology has been widely used to process fine structures on various materials, but there is no complete model that can describe the entire process. In this paper, the integral modeling process of abrasive water jet micro-machining (AWJM) is presented. The three-phase fluid dynamics model inside the nozzle and the surface evolution model are connected by theoretically calculating the jet erosive efficacy distribution before impacting the workpiece. Several improvements over previously presented models, such as taking into account the divergence angle of abrasive particles and the effect of the nonuniform distribution of each phase on the jet erosive efficacy, have been made. The model was used to predict the surface evolution of micro-channel profiles in 316L stainless steel and 6061-T6 aluminium. For both materials, the radial profile of erosive efficacy shows a normal distribution, and the erosive efficacy of 6061-T6 is two orders of magnitude higher than that of 316L. The results show that the model can accurately predict the profiles of the micro-channels resulting from AWJM. In particular, the average prediction error in the width direction is reduced to 4.5%.