Kerf Angle Research Articles

Abrasive water jet machining of fly ash and metakaolin based geo-polymers

In the present study, the abrasive water jet machining (AWJM) of geopolymers prepared from fly ash, metakaolin and sand is discussed. The samples were prepared from sodium promoter, fly ash / metakaolin and sand. The process of activation was made using a 10M sodium hydroxide solution combined with a sodium silicate solution (the ratio of liquid glass - 1:2.5). To produce geopolymers, flakes of technical sodium hydroxide were used and an aqueous solution of sodium silicate (R-145) with a molar module of 2.5 and a density of around 1.45 g/cm3 the tap water. The alkaline solution was prepared by means of pouring the aqueous solution of sodium silicate over the solid sodium hydroxide. The solution was mixed and left until its temperature stablised and the concentrations equalised, which took around 2 hours. The fly ash, sand and alkaline solution were mixed for around 10 minutes using a low-speed mixing machine (in order to obtain a homogeneous paste). The paste was allowed to dry in the shade. The paper investigates the AWJM studies on the prepared geopolymer specimens with varyied input parameters such as standoff distance (1.2 and 3 mm), water pressure (120, 140 and 160 MPa) and feed rate (5, 10 and 15 mm/min). The output parameters such as kerf angle and material removal rate (MRR) were studied with the varying combination of input parameters. From the results, the optimal parameters for machining the geopolymer composites were interpreted.

Influence of AWJM Parameter on GFRP Reinforced Nylon-6 Composite

This research article is aiming to comprehend the cause of Abrasive Water Jet Machining (AWJM) parameter on kerf angle of the polymer based composites. Direct extrusion method is adopted to fabricate the Nylon 6 – GFRP composites. L27 OA design is followed to carry out to study the behaviour of AWJM parameter Kerf Angle (Ka). Three parameters with three levels are formulated; the selected parameters are pressure of the jet, standoff distance and feed rate and output is Ka. Taguchi optimization tool is used to locate the optimal combination of the AWJM parameter. The maximum pressure, low feed rate and standoff distance are the beneficial for reducing the kerf angle. ANOVA is also employed to determine the contribution of each process parameter on kerf angle and it is found that pressure combined with standoff distance plays important role in reducing the Ka followed by standoff distance and feed rate.

Optimisation of AWJM Process Parameters for Machining Granite using PCA Methodology

In Abrasive water jet machining, abrasive particles along with high pressure water are used to intrude on the work materials ranges from soft to hard materials using high velocity jet. The process parameters considered in this research for machining the granite are pressure, standoff-distance and cut quality. Experimental investigation had been carried out, in order to identify the impact of varying the input machining parameters on the results like kerf angle, material removal rate and roughness of the machined surface. In this study, Taguchi’s Multi response technique namely principal component analysis had been used to optimize the input parameters of the abrasive jet machine to obtain the desired outcome on granite work piece and also to foresee the best optimal input machining values of abrasive jet machining such as pressure, standoff-distance and cut quality. For each sequence of Taguchi L9 orthogonal array, sufficient number of experimentations had been carried out. Then with the help of principal component analysis, optimal process parameters that influence the granite machining characteristics have identified and to validate the experimentation, confirmation tests also been carried out with required combinations of array.

The Machinability of Steels by Abrasive Water Jet

Abrasive Water jet machining (AWJM) is a Non-Traditional manufacturing process, were the material is expelled from the workpiece by effect erosion of pressurized high-speed water stream mixed with high-speed abrasives. There are such a significant number of procedure parameters influence with nature of the machined surface can be done by AWJM. The process variables are, the cross speed, water driven weight, remain off separation, rough stream rate and kind of grating are significant. This measures in AWJM are Surface Roughness (SR, Rate of Material Removal (RMR), Kerf angle, cutting depth. At the past, the survive completed from different kinds of steel was inproved and investigated on AWJM research by identifying with execution estimates checking and procedure control and process factor advancement. In this paper, a study undergoes on AWJM about feature pattern regarding various types of steels.

Performance Studies On Flax Fiber Reinforced Polymer Composites – An Effect On Fiber Orientation

The plant based nature fiber added as a reinforced material for so many structural applications. From this awareness of earlier research in this paper by changing orientation of fiber and the mechanical properties and machining performance of flax fiber evaluated. The preparation of composite polyester resin was used with varying layers of flax fibers. The hand layup technique was adopted to fabricate the composites. The main aim of this research is to find out the effect of the fiber orientation. Different fiber orientations were used like 0º, 30º, 45˚, 60˚, and 90˚. Mechanical properties, tensile and flexural strength and abrasive water jet machining also performed to study the kerf angle. It was found that 00 and 900 orientation exhibited the better performance.

Experimental investigations on abrasive water jet machining of nickel-based superalloy

Waspaloy is often used in aviation combustion chamber at extreme environments. Waspaloy is also a nickel-based superalloy with exceptional strength properties at a temperature of 980 °C. In this experimental investigation, waspaloy is used to analyse the kerf angle (KA), surface roughness (SR) and material removal rate (MRR) during abrasive water jet machining. The effect of various parameters such as traverse speed, abrasive flow rate, water pressure and stand-off distance on KA, MRR and SR was discussed. The striation formation was analysed for different set of process parameters. The striations were also analysed using atomic force microscopy. An attempt was done to relate the jet impinging angle and nature of striation formation. It was found that the increase in declination angle decreases the formation of striation during water jet process of waspaloy.

AWJM parametric investigation on hybrid composite produced through two step stir casting process

Abrasive Water Jet Machining (AWJM) is well known non-traditional machining process employed to machine difficult to cut materials with complex contours. The proposed research work deals with the machinability investigation of AA-2024-B4C-TiC hybrid composite through AWJM process. The machining characteristics as output responses for the analysis are Surface Roughness (SR), Material Removal Rate (MRR) and Kerf angle (KA). The effect of individual process parameters are water Jet Pressure (JP), Standoff Distance (SOD) and Traverse Speed (TS), these parameters holds higher degree of influence over output responses. The influence analysis shows the notable increment in the metal removal process with the increased SOD, TS and water pressure. Moreover, the optimal combination of process parameters and their contribution are determined through Grey Relational Analysis (GRA). The optimum parameters obtained from GRA are water jet pressure of 260 bar, stand-off distance at 1 mm and traverse speed of 20 mm min−1. Moreover, the most significant factor on affecting the responses were water jet pressure (82.17%) followed by the transverse speed (13.84%)

Surface morphology and parametric optimization of AWJM parameters using GRA on aluminum HMMC

Abstract Cutting force arises as a major problem in machining of Hybrid Metal Matrix Composites (HMMCs) using conventional machining owed to the presence of reinforcement materials. Hence a non-conventional machining process namely Abrasive Water Jet Machining (AWJM) is preferred. The objective of this project is to investigate the cutting performance of AWJM on Aluminum HMMCs. The cutting parameters such as pressure, standoff distance (SOD) and feed rate are analyzed based on the L27 orthogonal array and the machining parameters such as kerf angle, SR and MRR were intended. The optimal condition for the better cutting performance was defined by Gray Relational Analysis (GRA). The SOD was the most contributing parameter with 81.74% as determined by ANOVA. The erosion of surface was augmented due to the improved SOD which has been analyzed by SEM. The grooved lines and ploughing materials were occurred due to the presence of reinforcement particulates.

Predication of Kerf Width and Surface Roughness in Waterjet Cutting using Neural Networks

Abrasive waterjet cutting is one of the unconventional methods used to cut some of the difficult to cut materials. In certain materials this method has proved to give better results compared to the conventional methods. In this model the water jet cutting is done on hastelloy using the three parameters which are abrasive mass flow rate, traverse speed, and the stand-off distance. The mathematical modelling to predict the kerf width based on these three input parameters is discussed in this paper. As the relation between the input and the output parameter is non-linear in nature neural network back propagation algorithm is used for the prediction. Here the experiment is conducted using waterjet cutting machine and the data’s like surface roughness, metal removal rate, kerf width and the kerf angle data are collected. Both the input and the output parameters are fed to the neural network toolbox programmed in the MATLAB. After 1000 iterations it has been found that the prediction is closer to the actual value. The mathematical constants which is the weight matrix is used to test the new set of data for accuracy. It has been found that the prediction is more accurate compared to the conventional methods. This experiment is based Taguch’s design which uses the above three parameters to cut the material. This paper also discusses on the predication of surface roughness of hastelloy created due to the variation in these parameters.

Performance Analysis of Abrasive Water Jet Cutting Process in Carbon Fiber Epoxy Polymer Composite

Abrasive water jet machining is unconventional material removal process used to dissolve openings and cavities by the force of rough particles of the slurry on hard and materials. It is a non traditional machining process able to machine wide scope of hard to cut materials such as alloys, composite materials. This work explores the impact of different process parameters on kerf angle and amount of materials removed which are imperative execution measures in abrasive waterjet machining. The variable abrasive water jet parameters considered here include water pressure, nozzle diameter stand-off distance and abrasive flow rate. Experiments were conducted on carbon fibre reinforced polymer composites by varying these parameters. This work concluded that maximum abrasive jet pressure increase the material removal rate and minimum stand off distance (SOD) will decrease the kerf angle in carbon fibre composites.

Study on ASJ Cutting of TC18, Based upon Multivariate Nonlinear Regression and SA-BP-AGA

TC18 titanium alloy has been widely applied, but is considered as a difficult machining material. Taking the kerf angle as the quality criterion, this paper studied the cutting performance of TC18 by the use of an abrasive slurry jet (ASJ), based upon multivariate nonlinear regression and SA-BP-AGA. Cutting experiments were carried out according to the Taguchi orthogonal method. The experimental factors included traverse speed, standoff distance, pressure and slurry concentration, with five levels set, respectively. Meanwhile, a characterization method of the major influencing factors was proposed. A multiple nonlinear regression model and a back propagation artificial neural network (BP) prediction model, based on adaptive genetic algorithm (AGA), were established. The reliability was verified by statistics equations for the 22 groups of the fitting or training model and the three groups of experimental results. The BP-AGA and Simulated annealing algorithm (SA) were used to form a set of prediction optimization systems, called integrated SA-BP-AGA. Finally, the results showed that the main factor influencing the kerf angle is the slurry concentration. BP-AGA is easier to model, offers better robustness and is more accurate than a multivariate nonlinear regression model. The best kerf angle can be predicted by the integration system. The study results can improve the performance for the machining of TC18 by ASJ.

Effect of abrasive type on marble cutting performance of abrasive waterjet

Abrasives play a critical role in the erosion process of abrasive waterjet (AWJ). Therefore, they can significantly affect the performance and profitability of cutting. In the relevant literature, there is no comprehensive study investigating the effect of abrasive type on the rock cutting performance. The current study aims to fill this gap. Various abrasives (garnet, white fused alumina, brown fused alumina, silicon carbide, glass beads, and emery powder) are used on this basis. Marble samples are cut in the tests in which the cutting parameters are kept constant. Cutting performances of the abrasives are investigated based on some performance outputs (the cutting width, cutting depth, kerf angle, and surface roughness). The study revealed that the silicon carbide and fused alumina (brown and white) present higher cutting performances in terms of the cutting depth and kerf angle. It is also concluded that the abrasives produce similar cutting widths and the glass bead produces smoother cutting surfaces. Additionally, it is demonstrated that cutting performance of the AWJ is highly affected by abrasive density and hardness.

Optimization of Input Parameters of AWJM: Using three different Abrasives on MS2062

The objective of this work is to optimize input parameters of AWJM (Abrasive Water Jet Machining) such as Nozzle Transverse Speed (NTS), Abrasive Flow Rate (AFR) and Stand-off Distance (SOD) using three different abrasives Garnet, Brown Fused Alumina and White Aluminum Oxide on MS2062 and to compare their performance with surface finish, MRR and kerf angle. Experiments were conducted according to Taguchi’s design of experiments. Analysis of variance is conducted to investigate the influence of each parameter on responses Three controllable parameters of three levels are applied for determining the optimal responses The results revealed that NTS is a most significant factor for MRR among three abrasives followed by AFR and SOD, with regards to surface finish and MRR White Aluminum Oxide has emerged as a most strong abrasive followed by Brown Fused Alumina and Garnet. It is recommended, to achieve the better surface finish, less kerf angle and good MRR White Aluminum Oxide be used in place of Garnet which is mostly used by the industry today.

Analytical Modeling and Experimental Study on Machining of CFRP/Ti Stacks with Submerged Abrasive Waterjet Machining

Abstract The research includes analytical modeling and experimental study on precision machining of hybrid composite stacks with Submerged Abrasive Waterjet Machining (SAWJM) process. The analytical model predicts the rate of material removal during the SAWJM process. An in-house fabricated SAWJM setup is used to machine stacks of Titanium and Carbon Fiber Reinforced Polymer (CFRP). The study compares critical process parameters including grit size, machined cavity size, stand-off distance, and kerf angle in SAWJM and Abrasive Waterjet Machining (AWJM) processes are evaluated. It was found that SAWJM process has the capability of effectively machining CFRP/Titanium composites with high precision. The machined surface did not show any cracking and delamination about the edges and is free of thermal stresses. In this study, the standoff distance and the size of the abrasive grains have a noteworthy influence on the machining process. The cavities machined on both CFRP and titanium during SAWJM process are smaller and more circular than that produced during AWJM process. Both analytical model predictions and experimental results match within 10 % error. The results of this study provide a deeper insight into the precision machining of hybrid composite stacks.

Investigation to Appraise the Abrasive Water Jet Response of Curaua/Basalt Hybrid Polyester Composites

The application of natural fiber composite material in structural and interior parts of the automotive system is emerging. In this article an investigation is made to understand the effect of abrasive water jet machining parameters on surface roughness and kerf angle of the Curaua and Basalt fibers hybrid reinforced polyester composites. To identify the most effective machining parameter the MOORA and Principle Component method are used. It is found that jet pressure and feed rate are the most significant factors in influencing the surface roughness and kerf angle. Further, the effect of basalt content in the Curaua composites mechanical properties of Curaua composites, perhaps, a minor influence, is found with parameter optimization of basalt content.

Predicting correlations in abrasive waterjet cutting parameters of Lanthanum phosphate/Yttria composite by response surface methodology

The machining property of Lanthanum phosphate/Yttria prepared by the aqueous sol-gel process is evaluated using abrasive waterjet machine. Jet pressure, Stand-off distance, and traverse speed are taken as the governing parameters on material removal rate, kerf angle and surface profile roughness. Silicon carbide 80 mesh size is taken as abrasive. A linear cut is done on the composite of geometry Ø30 mm and 7 mm thickness for the L20 orthogonal array to study the process correlation that exhibits between the independent parameters. The equations are predicted through response surface methodology are evaluated. From the observations, jet pressure has found to have a significant effect on material removal rate and kerf angle whereas, traverse speed significantly affects surface profile to the greater extent. The microscopic examination of the kerf surface reveals the plastic deformation surface, wear track and presence of more numbers of valley and peaks regions in the top kerf surface. The study on this new functional composite will improve the utilization of the composite and will be a database for the researchers, to improve and extends the usage of the composite for different applications.

Study on fibre laser machining quality of plain woven CFRP laminates

Laser cutting is suitable for large-scale and high-efficiency production with relatively high cutting speed, while machining of CFRP composite using lasers is challenging with severe thermal damage due to different material properties and sensitivity to heat. In this paper, surface morphology of cutting plain woven carbon fibre-reinforced plastics (CFRP) by fibre laser and the influence of cutting parameters on machined quality were investigated. A full factorial experimental design was employed involving three variable factors, which included laser pulse frequency at three levels together with laser power and cutting speed at two levels. Heat-affected zone (HAZ), kerf depth and kerf angle were quantified to understand the interactions with cutting parameters. Observations of machined surface were analysed relating to various damages using optical microscope and scanning electron microscopy (SEM), which included HAZ, matrix recession, fibre protruding, striations, fibre-end swelling, collapses, cavities and delamination. Based on ANOVA analysis, it was found that both cutting speed and laser power were significant factors for HAZ and kerf depth, while laser power was the only significant factor for kerf angle. Besides, HAZ and the kerf depth showed similar sensitivity to the pulse energy and energy per unit length, which was opposite for kerf angle. This paper presented the feasibility and experimental results of cutting CFRP laminates using fibre laser, which is possibly the efficient and high-quality process to promote the development of CFRPs.

Effect of swirling abrasives induced by a novel threaded nozzle in machining of CFRP composites

This paper attempts at investigation of the feasibility of imparting a swirling motion to abrasive particles by introducing internal threads in the nozzle. In this investigation, a novel internal threaded nozzle was introduced in the abrasive jet machine to make holes on the carbon fiber reinforced polymer composites with the objective of reducing the machining time. This is a unique attempt of its kind and this innovation has brought down the machining time considerably and, as a consequence, higher material removal rate was obtained. Carbon fiber reinforced polymer composites are inhomogeneous and coarse in nature, and hence, the ease of machining and the machining time are always challenging. A morphological study was also made using an optical microscope to find the kerf width and kerf angles. The effect of two different nozzles on machining time, material removal rate, and kerf analysis on the carbon fiber reinforced polymer composite was investigated. It was found that machining time was reduced by 92% with novel internal threaded nozzle. The nozzle with internal threads also reduced the kerf angle of the machined hole.

Estimation of Optimal Process Parameters for Abrasive Water Jet Machining Of Marble Using Multi Response Techniques

Abrasive water jet machining has proven to be an effective non-Traditional machining technique which is used for cutting wide range of difficult to machine materials and obscure geometric profile. However, due to deprived surface quality there arises a need for post processing operations. Therefore, it is of prime importance to optimize the process parameter to obtain good surface finish economically. In the present work, machining parameters such as water jet pressure, stand-off distance (SOD) and transverse speed were optimized by considering multiple performance characteristics such as high material removal rate (MRR), good surface finish (Ra) and minimum kerf Angle (Ka). The experiments were designed using Taguchi’s Design of experiments and carried out on marble for each combination of (L27) orthogonal array. The optimal combinations of machining parameters were obtained using Taguchi Weightage method and Grey Relational Analysis. In general, both the analysis reveals that, material removal rate (MRR), surface roughness (Ra) and kerf Angle (Ka) is significantly affected by Transverse speed and Water jet pressure. Experimental results have shown that the output parameters have been improved considerably using this approach.

Preparation, characterisation and machining of LaPO<SUB align="right">4-Y<SUB align="right">2O<SUB align="right">3 composite by abrasive water jet machine

This article illustrates the work done on preparing a new ceramic matrix composite with the proportional concentration of Lanthanum phosphate (LaPO4) (80 wt.%) and Yttria (Y2O3) (20 wt.%) by aqueous sol-gel process. The prepared nano powder is compacted to 480 MPa at 28°C (room temperature) followed by sintering at 1,400°C for two hours to get the required disc shape geometry. The prepared ceramic matrix composite was machined using abrasive water jet machining (AWJM). Grey relational analysis (GRA) is performed with various input parameters like jet pressure (JP), stand-off distance (SOD) and traverse speed (TS) to measure the deviations in performance characteristics such as material removal rate (MRR), kerf angle (KA) and surface roughness (Ra). The significant correlations of these parameters were analysed by using analysis of variance (ANOVA). From the experimental work it is evident that SOD has significant contribution of about 60.89% and it affects the output performance characteristics to a great extent. Confirmation experiment is also carried out to validate the results.