Features and mechanism of abrasive water jet cutting of Q345 steel

Abstract

This paper attempts to disclose the cutting features and mechanism of the pre-mixed abrasive water jet (AWJ) on Q345 steel. For this purpose, several cutting experiments were performed on the pre-mixed AWJ and a Q345 steel plate. Besides, a numerical simulation model was established based on the smoothed-particle hydrodynamics (SPH) and finite-element method (FEM) and adopted to analyse the erosion features of the jet at different angles and pressures. The main conclusions are as follows: (1) There exists a pressure threshold, i.e. the jet pressure under which the abrasive erosion kinetic energy is just enough to induce material deformation. For the 80 mesh corundum abrasive particles, the pressure threshold of Q345 steel is 15∼17MPa. (2) The Q345 steel suffers from deformation and failure under the high-frequency and high-speed impinging of abrasive particles. The abrasive velocity is positively correlated with the erosion ability of the abrasive particles to induce material failure. (3) The variation in the jet angle changes the vertical and horizontal jet velocities and affects the erosion process of the jet. (4) For Q345 steel, the optimal jet angle is about 80°. At this angle, the jet deflection trend towards the non-material side is minimized without undermining the jet erosion ability in the vertical direction. The research findings provide new insights into the mechanism of the AWJ cutting.