Abrasive Water Jet (AWJ) technology is widely used in mining. To explore how rock heterogeneity and natural cracks affect rock fragmentation, a numerical model using the pixel method was developed ...for jet-induced rock breakage. This method effectively represents rock cracks and improves computational efficiency. The study found that AWJ causes more damage in rocks with natural cracks compared to Pure Water Jet (PWJ), with significant differences in damage extent. Under PWJ, intact rocks showed minimal fracturing, while rocks with natural cracks experienced increased crack depth, length, and number. However, under AWJ, the overall fracture levels were similar in both rock types. Notably, rocks with natural crack had longer cracks under AWJ, setting the stage for more extensive fragmentation. These results offer theoretical support for using water jets in mining extraction.
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•Utilizing a pixel-based modeling approach enhances computational efficiency.•The fracturing effects on intact and naturally cracked rocks were compared.•The effect of natural cracks on the macroscopic crushing patterns of rocks was investigated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Nowadays, advanced machining techniques are widely used for solving various issues in manufacturing operations that include machining high strength materials, production of complex shaped profiles, ...better surface features, capable of high levels of precision, miniaturization, reduction of waste and secondary operations and lower production time. Among the various advanced machining techniques, abrasive water jet (AWJ) machining has received more attention from researchers and practicing engineers in manufacturing industries due to its capability of extensive operations and excellent quality of the cutting edge obtained during this process much superior to others, is reported by previous researchers. AWJ process is classified into abrasive water injection jet and abrasive slurry jet on the basis of the different ways of mixing between abrasive and water. This study explores the researches made on Injection type AWJ machining process as it is widely accepted by researchers and Industries for solving various issues. Review articles on AWJ have been collected from the year of 1960–2019. Hence, this study provides a detailed report on AWJ machining process (majority of discussion on metals and their compounds) through demonstration of various studies on subjects that include performance and surface characteristics, hybrid processes, versatile operations, micro machining and medical applications. A literature survey of recent trends and their applications of AWJ process has also been documented. Optimization studies have been discussed with various techniques used in the AWJ machining process. This has been referred to in this paper. In addition, future opportunties in AWJ have been discussed including a demand for requirements in various fields. The entire collection of results are of help in finding the niche applications for manufacturing operations in future. The outcome of this paper would also support present and future researchers in the identification of the significant process parameters, work materials and advanced techniques for getting better results in AWJ machining process.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, a numerical model based on the coupling algorithm of SPH-FEM is established and verified by laboratory experiments, the fragmentation mechanism of granite impacted by the abrasive ...water jet is discussed. Compared with the experimental results, the error of erosion depth is less than 5.46%, the error of influence range around the punching is less than 3.89%, and the error of punching diameter is less than 7.16%. The numerical model shows that the material removal is usually caused by the diffusion around the jet stream, and the total amount is 84.06%. The results show that under the strong impact of the jet, it will penetrate all substances in the jet path. When the kinetic energy of the jet is decreases, the removal of materials usually follows the weak path, that is, through the cleavage plane of the feldspar grains and the contact interface between the mineral crystals.
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•A numerical model of heterogeneous granite is established.•The influence of granite minerals on the removal mechanism of AWJ is discussed.•The crushing process of granite impacted by AWJ is reproduced by simulation.•Two kinds of material removal forms of granite impacted by AWJ are described.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Machining silicon carbide (SiC) is challenging due to its brittle and maximum tensile nature. Lapping or laser beam are done with a high cost of manufacturing and low material removal rates. Water ...abrasive jet cutting is a promising candidate since the machining temperatures and processing force of ceramics are extremely low. Investigation into the abrasive water jet machining of silicon carbide is carried out in the present work.The variations in traverse speed while abrasive water jet cutting of silicon carbide and its effect on the surface roughness and kerf characteristics are studied. Silicon Carbide abrasive material is used as garnet consisting of 80 mesh. The surface roughness was calculated along with the depth of the cut made during the processing.The outcomes demonstrated that the traverse speed is more effective upon the surface roughness and is an important factor that damages the top kerf width and the kerf taper angle.Based on the hardness and thickness of the SiC plate, the taper angle is high, and for a feed rate of 10 mm/min, the surface roughness is low. Less thickness of the SiC plate could have a lower taper angle than with high thickness. The erosive force is provided by abrasive material along with the jet stream.Water abrasive fine jet could effectively machinate silicon carbide ceramic material with a better surface finish accurately. Suitable surface roughness with higher productivity can be attained with medium traverse speed.The effect of process parameters on kerf taper angle and top kerf width in the abrasive water jet machining of silicon carbide is explored, considering surface roughness as an important output parameter.
The present article focuses on mechanism of delamination and kerf geometry in abrasive water jet machining of carbon epoxy composite. In the present study, four process parameters of abrasive water ...jet machining namely hydraulic pressure, traverse rate, stand-off distance, and abrasive mass flow rate are considered. The experiments are performed on the basis of response surface methodology as a statistical design of experiment approach. Delamination in machined samples is observed by using scanning electron microscope. Analysis of variance is performed in order to investigate the influence of process parameters on delamination, kerf taper ratio, and kerf top width. It is found that delamination decreases with increase in pressure and abrasive mass flow rate and decrease in stand-off distance and traverse rate. Kerf taper ratio decreases with increase in pressure and decrease in traverse rate and stand-off distance. Kerf top width decreases with decrease in stand-off distance and increase in traverse rate. Based on analysis, mathematical models are developed to predict the maximum delamination length, kerf taper ratio, and kerf top width. Further, a multi-response optimization is performed on the basis of desirability function to minimize delamination, kerf taper ratio, and kerf top width.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
Hole making is an important phase in composite machining as structural applications of composites require assemblage. To do so, abrasive waterjet machining (AWM) is recommended by several fabricators ...and researchers. The quality of the holes produced in composites severely affects the durability of assembled structures. Hence, exploring this aspect is important. In this context, the current study investigates the influence of the AWM variables on GFRP composites. Here, cutting speed (V
c
), and abrasive flow rate (Q
ab
) are selected as input variables whereas the output attributes are the material removal rate (MRR), surface roughness (R
a
), roundness (R
o
), and cylindricity (C
y
). Initially, mathematical models (objective functions) are derived using statistics of nonlinear regression for correlating the aforementioned variables and output attributes. In the next phase, the study utilizes recently developed Rao algorithms i.e. Rao 1, Rao 2, and Rao 3 to determine the ideal machining condition as V
c
= 100 cm/min, and Q
ab
= 300 gm/min. The results were also compared with the JAYA and TLBO approaches in order to show the effectiveness of the proposed methodology and it was observed that exploration of Rao 1, Rao 2, and Rao 3 algorithms appears more fruitful in terms of computational time and effort.
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BFBNIB, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The use of stacked metal-fiber material system is limited by machining challenges due to micro and macro level distinction in material phases. This study explores the machinability of stacked Ti6Al4V ...and CFRP material system using Abrasive Waterjet technology (AWJ). AWJ controlled depth experiments were conducted for stacked Titanium and monolithic CFRP. A strong linear relationship was identified between jet power-to-speed ratio and penetration depth for CFRP and Titanium individually, which was further used to predict the penetration depth in stacked Ti-CFRP configuration. Issues such as kerf rounding at the interface, delamination in CFRP were addressed and optimal process conditions were identified. A simplified model to predict the penetration depth was proposed which was proven to be more effective than multivariate regression model.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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.
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•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.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Controlled depth milling of composites structures by abrasive water jet (AWJ) is a new area of machining being explored and knowledge on this is bare minimum. Hence it is essential to investigate ...surface quality and damage induced to ascertain their mechanical reliability. Here, the mechanism of material removal is manifested by erosive wear. In this study, carbon fiber reinforced plastic (CFRP) laminates are milled using AWJ process and surfaces generated by varying process parameters are characterized using roughness systems, X-ray tomography and scanning electron microscopy (SEM). SEM images reveal presence of damages in form of craters, ridges, broken fibers and embedded abrasive particles. Crater formation due to erosion phenomenon is affected by jet pressure. It is seen that the crater volume increases by around 500% when pressure varies from 80MPa to 140MPa. In the literature reviewed correlation between roughness of the machined surface and the mechanical behavior is ambiguous and remains an open problem. Hence, novel attempt has been made to analyze the influence of damage (crater volume) on tensile strength. Mechanical tests on specimens with varying surface texture and crater sizes reveals that tensile strength of machined specimens is more influenced by crater volume rather than surface roughness.
•First work on influence of abrasive water jet CFRP milling on mechanical behavior.•High jet pressure milling increases broken fibers which increase surface roughness.•Craters, broken fibers, ridges, debonding and grit embedment are major damages.•Quantified damage a better indicator of mechanical behavior than surface roughness.•Crater is the most influential damage form which depreciates the tensile strength.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, the particle flow inside the nozzle is simulated by Computational Fluid Dynamics (CFD) method and the numerical results are verified by experimental observation. The motion ...trajectories of incident particles in different regions are investigated through trajectory analysis. In addition, the erosion damage mechanism was analyzed by the surface morphology and impact characteristics of the main abrasion region. The results show that the particle impact position gradually moves forward as the particle incident position moves away from the inlet center. Sensitivity analyses showed that erosion rate was most sensitive to pump pressure; impact frequency, impact velocity and impact angle were most sensitive to particle size, pump pressure and particle size, respectively. Due to the low angle impact of particles, the corresponding erosion damage mechanism is micro-cutting.
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•The trajectories of particles incident from varying regions of the inlet are discussed.•The sensitivity of varying parameters to the impact characteristics was evaluated.•The mechanism of particle erosion on the nozzle was comprehensively elucidated.•The work contributes profound insights into the erosion behavior of AWJ nozzles.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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