Experimental and simulation study on the influence factors of abrasive water jet machining ductile materials

Abrasive water jet (AWJ) is a type of cold processing technology, and there are many factors affecting its machining effect. In this paper, a coupled Finite Element Methods-Smoothed Particle Hydrody-namics (FEM-SPH) numerical model was established to investigate the key influencing factors of AWJ machining ductile materials. The abrasive particles in the model were shaped as irregular polyhedrons, and the material properties of the abrasive particles as well as the influence mechanism of the fluid- structure interaction between the abrasive particles and the water were considered. The relative error range of experimental measured results and simulation predicted results is 22.77%-36.55%. Then, the effects of content and distribution of abrasive particles, the jet working pressure P, the traverse rate of nozzle Vtrav and the impingement angle alpha were systematically and quantitatively evaluated through two-way verification of experiments and simulations. It was found that: (i) Effects of stand-off distance (SOD) on the kerf profile and the quality of kerf surface was essentially determined by the content and distribution of abrasive particles. As the increase of SOD, the jet divergence gradually increases, and the kerf profile gradually changes from "U-shaped"to "V-shaped". (ii) Experiments and simulations demonstrate that the P has a linear increasing relationship with the maximum depth h of kerf profile, and the Vtrav has a linear decreasing relationship with the maximum depth h, while it has a linear increasing relationship with the jet trailing angle beta, which was independent of the ductile material type. (iii) The combined effect of Vtrav and alpha affects geometric parameters and surface quality of the kerf profile, under the same P, the depth of the cut surface obtained by backward cutting is only 72.1% of that of the forward cutting, while the quality of the cut surface of former one is higher than the latter one.(c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).