Bottom Kerf Width Research Articles

Influence of Process Parameters on Kerf Width in Abrasive Waterjet Machining of GFRP Composites

This study investigates the influence of process parameters on kerf width in abrasive waterjet (AWJ) machining of glass fiber reinforced polymer (GFRP) composites. The experimental analysis was conducted using a Taguchi L27 orthogonal array to optimize the machining parameters: pressure, feed rate, abrasive flow rate, and standoff distance. The top kerf width (TKW) and bottom kerf width (BKW) were measured to evaluate the impact of these parameters. Results indicate that higher pressures and abrasive flow rates generally increase both TKW and BKW due to enhanced material removal rates. Conversely, increased feed rates tend to reduce kerf widths, highlighting the importance of optimizing cutting speeds. Standoff distance exhibited a less pronounced effect but still influenced the kerf widths. The optimal parameters for minimizing TKW and BKW were identified, providing valuable insights for improving precision and efficiency in AWJ machining of GFRP composites. These findings contribute to the development of more effective manufacturing practices for high-performance composite materials.

Optimization and Prediction of Process Parameters during Abrasive Water Jet Machining of Hybrid Rice Straw and Furcraea foetida Fiber Reinforced Polymer Composite

In the last few decades, natural composite materials have been considered one of the highly sustainable ecological alternatives for reducing the consumption of synthetic materials. Today, research on natural fiber composites is the main thrust for their use in various industrial applications. Further, continuous research works are being carried out to utilize natural composites as an alternative to synthetic materials. However, the inhomogeneity of composites, delamination, fiber pullout, higher surface roughness (SR) and dimensional inaccuracy under traditional machining have led the attention towards non-traditional machining, such as abrasive water jet machining, to achieve high-quality components. Hence, in this study, an experimental analysis based on the design of experiments is conducted on the machinability of a hybrid rice straw/Furcraea foetida composite under abrasive water jet machining (AWJM). Further, the concentration of the rice straw and the AWJ process parameters are varied, and their effects on the quality of machining is evaluated. The experimental trials are designed based on the Taguchi L27 orthogonal array, followed by an analysis of variance (ANOVA). From extensive experimentations, the concentration of rice straw is observed to be the most contributing (93.5%) factor to the SR. The traverse speed (TS) shows the highest percentage contributions of 93.13%, 55.50 and 55.70% to the material removal rate (MRR) and the top (TKW) and bottom kerf widths (BKW), respectively. However, the interaction between the fiber concentration and traverse speed gives the maximum contribution (35.04%) to the kerf taper (KT). A second-order response surface model is generated to study the effects of the process parameters on the SR, MRR, TKW, BKW and KT in any experimental domain. Finally, the microstructural characteristics of the machined surfaces, such as micro-cracks, debonding, and fiber pullout, are discussed.

Modeling of abrasive waterjet generated kerf on the top layer of a multi-layered structure

Abrasive waterjet (AWJ) is an effective tool for manufacturing parts from multi-layered structures (MLSs) due to its capability in machining a wide range of materials. However, the challenge in employing AWJ in producing the desired kerf geometry in MLS can be attributed to the complex nature of the jet's interaction with multiple layers that possess different material properties. Hence, a model that captures the interaction of the jet with MLS, and predicts the whole kerf geometry is required to gain control over the kerf quality. On the other hand, the kerf generated in a layer is affected by the presence of preceding-/following- layers. In this context, it is essential to develop a comprehensive model for the prediction of kerf profile during the penetration of the jet in each layer. Although, several models exist to predict the process response (erosion depth, top ( w t ), and bottom kerf width ( w b ), kerf taper), very limited models available on kerf profile prediction. Further, neglecting the actual jet characteristics limits their ability to predict accurately. By considering the above, this work proposes a model for the prediction of the kerf geometry (profile and characteristics) in a single layer of MLS along with its kerf characteristics apart from considering the non-linearities, such as jet characteristics and the effects of AWJ process parameters . A discretized form of the jet, abrasives mass flow distribution, and their velocity in the jet plume to realize a more realistic model for predicting kerf geometry. Further, a new parameter, ' depth of damaged region ’ was defined towards realizing the w t . The model was evaluated by comparing the kerf geometry formed on mild steel (MS) and aluminum (Al) materials by using root mean square and mean absolute error. The proposed model was found to predict the kerf geometry accurately. • First model to predict AWJ generated kerf profile considering abrasive particle velocity profile and mass flow rate distribution. • Development of analytical model to accurately predict the complete kerf profile in a single layer cut by AWJs. • Erosion theories combined with discretization approach in the development of model. • Effective representation of the top kerf width in different materials based on depth of damaged region.

Empirical modeling and optimization of kerf characteristics in Nd-YAG laser cutting of Al 6061-T6 sheet

Al alloys are the second most useful metal worldwide after the steel due to its high strength-to-weight ratio and corrosion resistance properties. In the present scenario, for creating contours in the sheet metals with close tolerances and high precision, laser beam cutting is preferred. During laser beam cutting of Al alloys, the reflectivity of the alloy possesses some difficulties to absorb the laser light. Such problems can be avoided using the shorter wavelength laser. This paper presents the modeling and optimization of kerf characteristics in Nd-YAG laser cutting of Al 6061-T6 sheet. In this study, kerf width (top and bottom side) and top kerf deviation are considered as kerf characteristics which are the functions of lamp current, pulse width, pulse frequency, and cutting speed. Box–Behnken design has been used for conducting the experiments and the experimental results have been further used for developing the response surface models and optimizing the responses using response surface methodology and grey relational analysis, respectively. Application of grey relational analysis has reduced the bottom kerf width by 12.5% and 7.75% along with straight and curved cut profiles respectively.

EXPERIMENTAL AND STATISTICAL INVESTIGATION OF THE EFFECTS OF CUTTING PARAMETERS ON KERF QUALITY AND SURFACE ROUGHNESS IN LASER CUTTING OF Al 5083 ALLOY

In this study, the effect of cutting parameters on kerf quality and surface roughness in laser cutting of Al 5083 alloyed material was investigated both experimentally and statistically (Taguchi & Gray Taguchi). Experimental design was determined using the Taguchi L[Formula: see text] (21x 3[Formula: see text] orthogonal array. Experiments were carried out by using two different gas pressures (GP) (8 and 10 bar), three different cutting speeds (CS) (3500, 4000 and 4500[Formula: see text]mm[Formula: see text][Formula: see text][Formula: see text]min[Formula: see text] and laser power (P) (2600, 3100 and 3600[Formula: see text]W) in the cutting of Al 5083 alloyed material. As a result of the study, top kerf width (TKW), bottom kerf width (BKW) and average surface roughness (Ra) were measured as output parameter values. Using the measured top and BKW results, kerf taper (KT) was calculated. The lowest values of TKW, BKW, KT and Ra were 2.219[Formula: see text]mm, 2.010[Formula: see text]mm, 0.984∘ and 2.394[Formula: see text][Formula: see text]m, respectively. To determine the optimum values of laser cutting parameters for minimum output parameters, signal-noise (S/N) ratio, variance and regression analysis, validity experiments and GRA methods were used. When S/N ratios were examined, the most ideal cutting parameters were determined as A1B3C1 for TKW and BKW, A2B1C3 for KT and A2B3C3 for Ra. When the variance results were examined, it was determined that the most effective processing parameter for TKW, BKW and KT was at 46.04%, 50.58% and 56.45% CS, respectively, and the most effective processing parameter for Ra was laser power with 46.57%. According to gray relationship analysis, optimum laser cutting parameters for the smallest values of all output parameters were determined as A1B3C1. According to gray relationship analysis, optimum laser cutting parameters for the smallest values of all output parameters were determined as A1B3C1.

FEM modeling and simulation of kerf formation in the nanosecond pulsed laser engraving process

In the present study, a finite element method (FEM) simulation model is developed for nanosecond pulsed laser engraving process. The model’s novelty lies in the fact that it predicts the actual dimensions of the engraved geometry emphasizing the dimensional deviation due to the defects from kerf formation such as the sloped side walls instead of the intended vertical ones. Simulations were performed and the values of kerf taper angle, top kerf width and bottom kerf width were compared with the corresponding ones from experimental tests made using a LASERTEC 40 laser engraving machine and also were used for process optimization.

Multi-objective Optimization of Kerf-taper and Surface-roughness Quality Characteristics for Cutting-operation On Coir and Carbon Fibre Reinforced Epoxy Hybrid Polymeric Composites During CO2-Pulsed Laser-cutting Using RSM

Current research focuses on optimizing various quality characteristics for kerf geometry generated through laser cutting of Coir fibre/carbon fibre/epoxy resin hybrid composite adjacent to straight cut profile employing pulsed CO2 laser system. The Kerf taper (KT) and the Surface roughness (SR) are the main quality parameters discussed. Dependent on significant process parameters, namely gas pressure, cutting speed, pulse frequency and pulse width predictive models were developed. In accordance with Taguchi's L9 orthogonal array (OA), the cutting trials are designed. Process-parametric optimization was performed using Response Surface Methodology (RSM). Furthermore, experiments were performed to obtain experimental data for the analysis of cut quality features. The impact of the input variables on the response characteristics is also explored. The morphological characterizations have been performed to analysis the effect of machining-variables and cut-quality for the top and bottom kerf widths with various laser cutting variables in the pulse laser-cutting of Coir-fibre/carbon-fibre/epoxy-resin hybrid composite. For SR and KT, the developed second order surface response model was found very successful. The optimal levels of cutting variables for KT are established at Gas pressure-6 N/mm2, pulse width-2.04 ms, cutting speed-8.01 mm/s, pulse frequency-15 Hz, for sample A1, Gas pressure-5.47 N/mm2, pulse width-2.5 ms, cutting speed-8.81 mm/s, pulse frequency-8.43 Hz, for sample A2, Gas pressure-3.85 N/mm2, pulse width-1.5 ms, cutting speed-9.06 mm/s, pulse frequency-5 Hz, for sample A3 additionally for SR Gas pressure-2 N/mm2, pulse width-1.5 ms, cutting speed-7 mm/s, pulse frequency-5 Hz, for sample A1, Gaspressure-2.36 N/mm2, pulse width-1.5 ms, cutting speed-7 mm/s, pulse frequency-15 Hz, for sample A2, Gaspressure-6 N/mm2, pulse width-1.5 ms, cutting speed-11 mm/s, pulse frequency-8.73 Hz, for sample A3. Regression results and linear and square impact of laser cutting variables have been revealed to be important to validate the model.

A study of kerf quality of Inconel 718 using abrasive water jet cutting

This study shows the experimental investigation on Inconel 718 to find the parametric response of abrasive water jet cutting on top Kerf width (Wt), bottom Kerf width (Wb) and Kerf wall inclination. The machining are planned with Box Behnken Design (BBD) based on four factors at three levels each. Four important process parameters e.g P, AFR, SOD and TS, were selected in cutting. The quadratic regression models were established to forcast the Kerf quality by using response surface methodology. ANOVA has been employed to find the influence of operating factors. Result reports that traverse speed is the most influenced parameter in affecting the Kerf taper.

Kerf Analysis and delamination study on fiber reinforced composites cut by abrasive water jet

Abrasive water jet machining is a non-conventional machining process that is used in automobile, aircraft, chemical processing equipment, marine, spacecraft and sporting goods industries related applications. There has been a growing interest in using composite materials in place of conventional materials due to their unique properties, such as extremely high strength to weight ratio and corrosion resistance. As a result, these materials are being used in aerospace and aeronautical structural applications. Abrasive water machine has capability to cut almost plethora of materials owing certain advantages such as no additional tools are required, no cleaning is required as it self-cleaned, fast set-up, etc. because of this characteristic’s, the attention of AWJM has attracted industries over unconventional machines. Glass fibre which covers under polymer matrix composite is considered in this experimental work. This paper evaluates an experimental study on three different thickness of laminated plates, pressures, stand-off distance and traverse rate are different parameters used for design of experiments. Top kerf width, bottom kerf width and kerf taper are the machining process responses which has been evaluated using analysis of variance (ANOVA) technique. Delamination studies have been done using Scanning Electron Microscope (SEM).

Accuracy and surface quality of abrasive waterjet machined CFRP composites

The use of carbon fiber-reinforced composites is increasing today since they have an excellent weight-to-mechanical properties ratio. Traditional machining of this material is difficult. Abrasive water jet machining (AWJM) is an advanced non-traditional material removal process that can machine hard-to-cut materials. The process is widely used in aerospace, marine, and automotive industries. However, it encounters several challenges when cutting carbon fiber reinforced polymers (CFRP). The present work aims to study the characteristics of AWJM of CFRP laminates. Detailed experimental investigations are conducted to explore the effect of traverse feed and standoff distance (SOD) on top kerf width, bottom kerf width, kerf angle, profile area, volumetric removal rate, and the average surface roughness, and jet deviation factor. Repeatability tests are also used to assess the kerf dimensional accuracy and surface roughness tolerance achieved by AWJM of CFRP laminates. Results showed that the surface roughness increases along with the cut thickness, especially at large traverse feed and SOD. Both the kerf taper angle and the volumetric removal rate increase with traverse feed and SOD.

The Effect of Laser Parameters on Cutting Metallic Materials.

This experimental study investigated the effect of laser parameters on the machining of SS41 and SUS304. The metallic materials play an important role in engineering applications. They are widely used in high-tech industries such as aerospace, automotive, and architecture. Due to the development of technology and high-tech industrialization, the various processing technologies are being developed with the requirement of high precision. However, the conventional cutting process is difficult to meet high precision processing. Therefore, to achieve high precision processing of the SS41 and SUS304, laser manufacturing has been applied. The current study investigated the process quality of laser cutting for SS41 and SUS304, with the usage of a continuous wave CO2 laser cutting system. The experimental variables are set to the laser cutting speed, laser power, and different engineering materials. The results are significantly affected by the laser parameters. As the result, the process quality of the laser cutting has been observed by measuring the top and bottom kerf widths, as well as the size of the melting zone and Heat Affected Zone (HAZ) according to volume energy. In addition, the evaluation of the laser processing parameters is significantly important to achieve optimal cutting quality. Therefore, we observed the correlation between the laser parameters and cutting quality. These were evaluated by analysis of variance (ANOVA) and multiple regression analysis. The experimental results of kerf top, kerf bottom, melting width, and HAZ on the laser parameters are properly predicted by multiple regression. In addition, the effect of laser parameters on the materials is determinant by the percentage of contribution of ANOVA.

An Experimental Analysis of Cutting Quality in Plasma Arc Machining

Plasma arc cutting (PAC) is an unconventional process widely used in manufacturing of heavy plate products. This work reports on the research results of machining quality of the workpiece in the plasma arc cutting on the low carbon low alloy steel. An experimental investigation of the characteristics of machining accuracy and surface integrity was carried out for basic machining parameters (cutting speed, arc current, arc voltage, plasma gas pressure, stand-off distance and nozzle diameter). The kerf geometry was determined with three accuracy parameters (top kerf width, bottom kerf width and kerf taper angle). The parameters of deviation present due to plasma curvature were defined by drag and pitch of drag line. The surface roughness was determined with two main roughness parameters through scanning the surface topography (roughness average and maximum height of the profile). The surface properties were determined over microstructure in heat affected zone (HAZ). The results show an acceptable machining quality of the PAC, so that this process is an excellent choice for fast and efficient material removal. However, the plasma arc cutting is not suitable for the final machining because of the metallurgical variations in the HAZ.

Optimization of multiple kerf quality characteristics for cutting operation on carbon–basalt–Kevlar29 hybrid composite material using pulsed Nd:YAG laser using GRA

Fibre-reinforced polymers are utilized for different industrial applications. Hybridization of such fibre polymers aids in upgrading their performance. Kevlar-29, basalt fibre, and carbon fibre find tremendous use in automotive, defense and aerospace industries. These applications require precision machining with very close tolerances. In this research, such an attempt has been made to measure the values of top kerf width, and bottom kerf width, cut with a pulsed Nd:YAG laser on a 1.92mm thick hybrid composite laminate having fibre volume fraction of 55.2%, and further optimize them using grey relational analysis. Input parameters such as pulse width, gas pressure, lamp current, standoff distance, and cutting speed have been experimentally varied for 42 combinations which have been designed with the help of Box Behnken design. Effects of parameters individual contribution towards the kerf quality have been discussed. With the help of grey relational analysis, optimal results were obtained at lamp current of 200A, pulse width of 2.5ms, 2mm of standoff distance, compressed air pressure of 12kg/cm2 and cutting speed of 200mm/min. The values of the kerf width showed a significant reduction of 15.28% and 12.81% when optimal values of input parameters were used.

Machinability and Delamination Studies on Glass Fiber Reinforced Polymer Matrix Composite Cut by Abrasive Water Jet Machine

Abrasive water jet machining possesses inherent technological and manufacturing advantages unmatched by most machine tools. They are generally used in automotive, marine and aerospace industries for machining of composites. However, abrasive water jet cutting of GFRP laminates possesses several challenges, such as surface finish and delamination of the cutspecimen. Henceforth, more experimental work is needed to provide sufficient machinability databases for manufacturing industries. This paper presents an experimental study for cutting GFRP laminates. Different AWJM conditions including pressure, traverse speed and abrasive flow rate are analyzed using full factorial design of experiments. Machining process responses such as surface roughness (Ra), top and bottom kerf width, kerf taper, delamination of fibers have been evaluated using analysis of variance (ANOVA) technique. The optimum process parameters for AWJM of glass fiber reinforced polymers have beensuggested.

Simulation, statistical modeling, and optimization of CO2 laser cutting process of polycarbonate sheets

Laser cutting well-known as a manufacturing process is a rapid, repeatable, and reliable method that is frequently used for cutting various materials such as thermoplastics. Due to their physical and chemical properties such as fatigue resistance, high toughness, and re-melting properties, thermoplastics such as polycarbonate are widely used in automotive parts, electronics, etc. In this study, a numerical simulation of the laser cutting process by a finite element method is developed. The sample simulated in this research is a 3.2 mm thick Polycarbonate sheet that is subjected to the laser cutting process by a low power continuous CO2 laser. The effects of the laser cutting process parameters such as laser power, cutting speed, and laser focal plane position on the top and bottom kerf width, top heat-affected zone, the ratio of upper kerf width to lower kerf width and taper kerf are investigated by statistical techniques of variance analysis. Choosing an appropriate Gaussian distribution is studied as well. The results show that the laser scanning speed has a significant effect on the top kerf width. By choosing a cutting speed of 20 mm/s and a focal length of -3, the taper kerf is minimized. By increasing the laser cutting speed from 4 to 20 mm/s and decreasing the laser power from 50 to 20 W, the heat-affected zone decreases. The developed analysis can predict the depth of kerf in a continuous mode for different values of laser power, speed, and laser focal plane.

Post-Processing of FDM 3D-Printed Polylactic Acid Parts by Laser Beam Cutting.

In this paper, the post-processing of 3D-printed poly lactic acid (PLA) parts is investigated. Workpieces are manufactured by fused deposition modeling (FDM) 3D printing, while they may have defects in some areas such as edges. A post-processing is introduced here for 3D-printed samples by low power CO2 laser. The thickness of the FDM samples are 3.2 mm and printed by optimum conditions. Effects of process parameters such as focal plane position (−3.2–3.2 mm), laser power (20–40 W), and laser cutting speed (1–13 mm/s) are examined based on the design of experiments (DOE). Geometrical features of the kerf; top and bottom kerf; taper; ratio of top to the bottom kerf are considered as output responses. An analysis of the experimental results by statistical software is conducted to survey the effects of process parameters and to obtain regression equations. By optimizing of the laser cutting process; an appropriate kerf quality is obtained and also optimum input parameters are suggested. Experimental verification tests show a good agreement between empirical results and statistical predictions. The best optimum sample with 1.19 mm/s cutting speed, 36.49 W power and 0.53 mm focal plane position shows excellent physical features after the laser cutting process when 276.9 μm top and 261.5 μm bottom kerf width is cut by laser.

Experimental investigation and fuzzy logic modelling of CO<SUB align="right">2 laser cutting parameter for AA6061-T6 sheet

The laser machining is a thermal energy-based process. The aluminium alloy is a highly reflective material which is difficult to cut by using the laser cutting process. The present paper experimentally investigated about the CO2 laser cutting of aluminium AA6061-T6 alloy material for the improvement of geometrical accuracy of the curved profile at the same time to minimise the top, bottom kerf width and kerf deviations. The experiments are carried out by using fuzzy logic approach and to predict the effect of CO2 laser cutting quality based on the cutting parameters on laser power, cutting speed, gas pressure and focal position. The fuzzy logic model is used on fuzzy logic tool box of MATLAB using Mamdani technique. The relationship between experimental value and fuzzy model are compared. Finally, based on the results, the proposed fuzzy logic models are minimised to top, bottom kerf width and kerf deviations of CO2 laser cutting of AA6061-T6 aluminium alloys.

Optimizacija karakteristika kvaliteta reza kod rezanja laserom BFRP kompozita korišćenjem genetskog algoritma baziranog na grej relacionoj analizi

In laser beam machining, the geometrical precise cutting of fiber reinforced polymer (FRP) composite materials is a challenging task in order to produce a higher quality cut. The aim of the present research is to determine optimum levels of cutting parameters able to provide geometrically accurate cut for 1.60 mm thick Basalt Fiber Reinforced Polymer (BFRP) composite laminate. The total of 42 experiments have been performed on a 250W pulsed Nd:YAG laser system. During experimentation, the lamp current, pulse width, pulse frequency, compressed air pressure and cutting speed have been varied to evaluate different kerf quality characteristics such as top and bottom kerf width, top & bottom kerf deviation, and kerf taper. Experimental results have been used to single index optimization of evaluated multiple kerf quality characteristics. A hybrid grey relational analysis coupled with genetic algorithm approach has been adopted for the optimization. The optimum levels of cutting parameters have been found at moderate lamp current (184.5 Amp), lower pulse width (2 ms), compressed air pressure (8 kg/cm²) and cutting speed (50 mm/min) and higher pulse frequency (30 Hz). Finally, confirmation experiments have been conducted and it has been observed that optimal levels of cutting parameters are able to improve top kerf width, bottom kerf width, top kerf deviation, bottom kerf deviation, and kerf taper by 13.33 %, 13.29 %, 23.52 %, 23.07 %, and 10.83 %, respectively. From the experimental results, it has been found that lamp current is the most significant parameter for all kerf quality characteristics.

Investigation of optimal process parameters for laser cutting of Inconel-718 sheet

Precise machining of advance material like Inconel-718 is an emerging need. Selection of an appropriate optimal range of cutting parameters is quite essential to achieve the high-quality cut and is a challenging task within this domain of study. The aim of this research is to develop a robust prediction model, which can suggest the desired range of cutting parameters for accomplishing better cutting quality, precision, and geometrical accuracy. Experiments have been performed on a 300 W (CNC-PCT 300) pulsed Nd: YAG laser cutting system at various levels of input cutting parameters, namely gas pressure, standoff distance, cutting speed, and laser power. Thereafter, response surface methodology has been adopted to develop mathematical models in terms of aforementioned input cutting parameters for geometrical quality characteristics: top kerf width and bottom kerf width. These developed models have been validated by comparing the predicted values with the experimental ones. Further, these models have been optimized using the multiobjective genetic algorithm in order to ascertain the optimal range of cutting parameters pertaining to better quality cut with high precision and geometrical accuracy.

Improving laser cutting quality of polymethylmethacrylate sheet: experimental investigation and optimization

Motivated by the need to enhance the kerf quality during cutting of Poly(methyl methacrylate) (PMMA) sheets using pulsed CO2 laser beam, this study presents an experimental investigation and optimization of laser cutting parameters including cutting speed, assisted gas pressure, laser beam power, and sheet thickness. The kerf quality characteristics including the top kerf width, bottom kerf width, and kerf taper have been considered as the process responses and have been measured using polarized light microscope. The experiments were designed and planned using Taguchi L18 orthogonal array with a mixed design. The effects of different cutting parameters on the kerf characteristics have been statistically analyzed using analysis of variance technique (ANOVA). The obtained results revealed that any increase in cutting parameters will result in increasing the top and the bottom kerf widths, while increasing cutting speed or laser power results in increasing the kerf taper. Second order regression models have been developed to model different kerf characteristics as functions of the process parameters. Genetic algorithm (GA) has been used to select the optimal cutting parameters using the developed regression model as an objective function to minimize the kerf taper. A considerable improvement in kerf quality has been achieved and the obtained results have been verified using confirmation experiments. The application of the proposed approach is capable to reduce the kerf taper from 1.92° to 0.02° while maintaining the minimum kerf width at a reasonable value (less than 0.5 mm).