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In recent years, more and more researches have been carried out on the erosion mechanism of abrasive particles on target materials in the abrasive waterjet cutting process. However, the effect of material property factors on the target erosion damage is rarely studied systematically. In this work, a 3D smoothed particle hydrodynamics-finite elements model is established for the simulation. The controlled variable method is used to study how each material property factor affects the erosion process of single abrasive particle and to find out the key material property factors of Al6061-T6 and Ti-6Al-4V. The influence of the interaction of the key material property factors on the target erosion damage is further evaluated using the orthogonal test method. [ABSTRACT FROM AUTHOR]

On the basis of experimental verification, the methods of smooth particle hydrodynamics (SPH) and finite element methods (FEM) were used to study the process of abrasive jets cutting rock under confining pressure conditions. The results show that the failure of rock was mainly due to compressive and shear stresses, while the propagation of cracks was dominated by tensile stress. Under confining pressure, the cracks in rocks were mainly horizontal. The damage depth significantly decreased with increasing confining pressure, while the damage width first decreased and then increased. The critical distance between two slits without penetration is four times the diameter of the abrasive jet. When the cutting direction of the abrasive jet was perpendicular to the maximum stress, the relief range of the confining pressure formed was larger. The results have certain guiding values for revealing the mechanism of abrasive jet impact rock breaking and engineering applications. [Display omitted] • The process of an abrasive jet moving cutting rock under confining pressure was studied. • The unloading of confining pressure during abrasive jet cutting of rocks was studied. • Analyze the optimal spacing of abrasive jet cutting from the aspect of crack penetration. • By comparing and analyzing the influence of confining pressure factors on crack propagation. [ABSTRACT FROM AUTHOR]

Use of abrasive water jet (AWJ) to break rock is a promising technology for improving the speed of tunnelling hard rock roadways. In this study, smooth particle hydrodynamics (SPH) and the finite element method (FEM) were coupled to develop a method that was used to simulate the abrasive water jet slit rock. The failure patterns and crack evolution were analysed. Moreover, the effects of parameters of AWJ on rock slit were studied. Furthermore, the motion behaviour of abrasive particles after collision with hard rock is discussed. The results indicated that the optimum mass concentration and diameter of AWJ were 15% and 1.6 mm, respectively, and the depth of slits cut in rocks increased nonlinearly with increasing pressure. Instantaneous failure and multi-step cumulative failure occurred at the centres and edges of rock fractures, respectively. For impacts at large incident angles, the cumulative damage velocities were greater for the central cracks than the radial cracks. The impact velocity had the greatest effect on the propagation of the central cracks, while the effect on the radial cracks was relatively small. The equivalent stress caused by impact was the primary reason for the failure of rock elements at the main impact site, and the cracks in rock were mainly caused by tensile stress. The damage of rock elements accumulated in steps similar to the shape of stairs. Damage accumulated faster when the pressure peak was large and the pressure undulated frequently. The findings of this study provide a theoretical reference for optimizing the parameters of AWJ and increasing the speed of excavating in hard rock. [Display omitted] • The best parameters of abrasive water jet rotating grooved rock were determined • The damage features of rock slits include instantaneous damage and stepped rise. • The central crack is sensitive to the impact angle, and the damage raises faster. • Multiple factors caused rock damage, and crack mainly depends on the traction. [ABSTRACT FROM AUTHOR]