Drilling Of Composite Materials Research Articles

A vision-based hole quality assessment technique for robotic drilling of composite materials using a hybrid classification model

A vision-based hole quality assessment technique for robotic drilling of composite materials using a hybrid classification model

Evolutionary Algorithms for Optimization of Drilling Variables for Reduced Thrust Force in Composite Material Drilling

This study aims to optimize drilling variables to reduce the thrust force required for drilling composite materials. The optimization process involves using evolutionary algorithms such as particle swarm optimization (PSO) and genetic algorithm (GA) to determine the best combination of drilling parameters, including drill speed, feed rate, and point angle. The objective is to minimize the thrust force required for drilling while maintaining the desired quality of the drilled holes. ANOVA and regression analysis is implemented to discuss the impact of drilling variable on the thrust force. The results demonstrate that the proposed approach is effective in reducing thrust force and improving drilling efficiency. The optimized drilling parameters obtained can be used to enhance the performance of composite material drilling processes. Performance output of both algorithms for optimization of problem is discussed in detail.

In-situ temperature monitoring during rotary ultrasonic-assisted drilling of fiber-reinforced composites

Drilling polyetherimide composite is difficult due to the anisotropic and inhomogeneous structure of fiber and matrix. Drilling of fiber-reinforced composites is a thermo-mechanical friction procedure required in various aerospace and automotive applications. The major reason for component rejection during manufacturing processes is due to thermal damage and temperature elevation defects such as delamination and fiber pullout caused during drilling. This work aims to propose a rotary ultrasonic-assisted drilling technique for composite materials to reduce thermal damage using diamond-impregnated tools. The influence of drilling parameters such as rotational speed, feed rate, abrasive grit size, and ultrasonic power was monitored on temperature elevations. The temperature was monitored using thermocouples located at different distances of 1.0, 2.0, and 3.0 mm from the main drilled hole. The response surface methodology was used for the design of experiments during the drilling of composite material and optimization of process parameters was carried out using analysis of variance. Rotational speed and abrasive grit size were observed to have the highest contribution of 42% and 37% for temperature elevations respectively. It was witnessed that temperature increases with an increase in rotational speed, feedrate, and abrasive grit size. Increasing the ultrasonic power during drilling temperature can be minimized. The temperature elevations at the tool-composite interface can be reduced by leveraging the application of rotary ultrasonic-assisted drilling.

Effect of drilling process parameters on delamination factor in drilling of pultruded glass fiber reinforced polymer composite

Drilling of FRP composite materials finds widespread applications in many engineering fields but the Fiber breakage, delamination, spalling, pull-out, fuzzing are some of the difficulties This distinguishes FRP composite material drilling from ordinary material drilling. In the current work, The Pultruded glass fiber reinforced polymer composite (PGFRP) with hybrid filler produced at optimum pultrusion process parameters. Drilling characteristics such as drill bit lip angle, spindle speed, and feed rate have all been studied in view of delamination factor in the PGFRP composites with hybrid filler. Taguchi's single response optimization approach was used to find the best drilling parameters. It was found That optimum drilling parameter for optimal delamination factor in the PGFRP composite of given composition are spindle speed 3000 rpm, feed rate 200 mm/min and 1000 lip angle of twist drill.

Effects of drilling parameters on delamination of kenaf-glass fibre reinforced unsaturated polyester composites

Drilling is a secondary material removal and usually carried out to facilitate fastening of parts together. Drilling of composite materials is not usually a problem-free process. Issues related to delamination composite laminates need to be addressed because it introduces the stress concentration point on the composite. This study focussed on the influence of process parameters such as spindle speed, feed rate, type of drill bits and geometry on the extend of delamination experienced by the composite during the drilling process of kenaf-glass fibre-reinforced unsaturated polyester composite, and the delamination measurements were taken under a microscope. Taguchi methods and analysis of variance were employed to find the optimal parameters. From the results, the most significant parameter was the feed rate. The minimum delamination was achieved when the feed rate was 0.05 mm/rev and spindle speed was 700r/min using both types of drill bits. The quality of the drill hole using the twist drill bit has been proven to be better than the brad drill bit.

Delamination evaluation in drilling of composite materials – A review

The persisting challenge for adaptable composite material, to make a remarkable material property along with lighter and stiffer parts. This leads to a wider application of composite materials (CFRPs and GFRPs) due to its better adaptability and predominant properties. Mechanical drilling is inevitable mode of operation and it’s always challenging and difficult for CFRP which leads to various onset damages. Drilling originated delamination at entry and exit of hole is most undesirable and defying damage leads to material rejection. Delamination assessment is always important for correction and improvement of assemble parts to achieve highest performance index. During last few decades, various delamination factors have been derived and suggested as a point of reference for delamination measurement and meanwhile various delamination assessment techniques are being proposed to measure the severity of delaminated zone for evaluation of delamination. This state-of-art review paper summarizes various delamination quantification and measurement techniques for the correction and improvement of drilling approach reported in open literature. It can be referenced not only as an up-to date summary available form past results but also possibilities for future scope to subdue delamination during drilling in CFRP.

Investigation of effect of abrasive water jet (AWJ) machining parameters on aramid fiber-reinforced polymer (AFRP) composite materials

PurposeThe purpose of this study was to optimize the surface roughness (Ra), delamination damage at the hole entrance (FdT) and at the hole exit (FdB) and kerf angle (K) in the drilling of aramid fiber-reinforced polymer (AFRP) composite material using abrasive water jet (AWJ) machining.Design/methodology/approachThe AFRP composite was produced by the vacuum infusion method. The drilling experiments were performed on an AWJ machine using a three-axis computerized numerical control system. Machine processing parameters were determined as water pressure (2,000, 3,000 and 4,000 bar), stand-off distance (2, 4 and 6 mm) and traverse feed rate (150, 250 and 350 mm/min). Optimization of processing parameters in the drilling experiments was carried out according to the Taguchi L27 (33) orthogonal array. In addition, gray relational analysis (GRA) was used to analyze the complex uncertainty affecting the results.FindingsResults of the drilling operations demonstrated that water pressure (P) was the most effective parameter, with 65.3%, 65.2%, 49.8% and 52.1% contribution rates for Ra, FdT, FdB and K, respectively.Practical implicationsReliable results have been obtained with Taguchi-based GRA while drilling AFRP composite material using AWJ. Significant results have been achieved to increase the hole quality in the drilling of AFRP composite material.Originality/valueThe new approach is to present more detailed analysis by using Taguchi method and multi-decision Taguchi-based gray relation analysis in AFRP composite material drilling using AWJ. Thus, time and experiment costs are saved.

Study on dedicated drill bit design for carbon fiber reinforced polymer drilling with improved cutting mechanism

Carbon fiber reinforced polymer (CFRP) has significant applications in the aerospace and automobile industries. However, the relatively high thermomechanical loads generated when drilling CFRP is considerably detrimental to the cutting tool. To address this issue, in this work, a step-change in the performance of CFRP drilling was conducted by switching the cutting model from crushing/compression fracture to the shear cutting of the composite workpiece to suppress the thermomechanical loads using a novel web thinning design. To evaluate the performance of the proposed drill bit, a comprehensive comparison was carried out between the dedicated and conventional drill bit designs from thermal, mechanical, and chip formation points of view. The results show that the dedicated drill bit outperformed the conventional drill bit in terms of thrust force, temperature elevation, burr, and exit-delamination. An in-depth observation revealed that the shear cutting became dominant in the drilling with the proposed drill bit while the crushing/compression was dominant with the conventional drill bit. The transition of the phenomena was induced by the properly designed rake angle. The mechanism of material removal in CFRP drilling using the dedicated drill bit design provides a new design direction to modifying the rake angle for improving the efficiency and quality of composite material drilling.

Analytical study of delamination damage and delamination-free drilling method of CFRP composite

Abstract Drilling of composite materials is a challenge in aviation and aerospace field. Delamination often occurs at the hole exit which can reduce the strength of the structure. In this study, to reduce delamination, an analytical model with thermal effect is proposed to predict critical delamination condition of composite. Anisotropy of the composite, thermos-mechanical deformation and load cases of the tool are taken into consideration. Numerical simulation and punching experiments with accurate uncut plies are conducted to validate the rational of the analytical model. The value of critical thrust force and the effect of drilling temperature on that are obtained from the model. In addition, a thrust force model based on the tool geometry is presented with the feed rate per tooth. According to the proposed model, critical feed rate per tooth for delamination-free drilling with different uncut plies and drill diameters can be obtained

Effect of adding a woven glass ply at the exit of the hole of CFRP laminates on delamination during drilling

Composite materials are increasingly used in the aeronautical field. The assembly of structures requires usually drilling of composite parts. Drilling of composite materials generates defects, mainly delamination at the exit of the hole. This major defect diminishes the structure strength. Delamination is directly related to the drilling thrust force. Minimizing this force reduces the defects. Adding a woven glass ply at the exit of the hole is found to be another adequate solution to reduce the defects. In this paper, the drilling of carbon/epoxy thick composite structures with a woven glass ply at the exit of the hole is considered. An analytical model is developed to determine for a given tool geometry the critical delamination forces as function of the number of non-drilled plies remaining beneath the tool. The results are validated experimentally. These results show that adding a woven glass ply at the exit of the hole reduces delamination.

Effect of Cutting Parameters on Surface Roughness in Drilling of Al-SiC-Gr Composites Using RSM and Fuzzy Logic Modeling Method

Main aim of this paper is to analyze the machining a parameter a way to influence on surface roughness throughout drilling of composite material. During this test nearby the impact of speed and feed on drilling the composite. The drilling experiments were progressing to by CNC machine with solid carbide drill at a variety of spindle speeds and feed rates. Surface roughness of the drilled hole was investigated in Al-SiC-Graphite composite, the take a look at outcomes exhibit that the feed rate has more control on surface roughness. Surface roughness is considered as investigation result, and it is anticipated utilizing fuzzy logic. The predictable surface roughness values are compared with test outcome and response surface model. The outcomes decide that anticipated surface roughness values esteems ably by fuzzy modeling technique.

Multi-objective optimization analysis of cutting parameters when drilling composite materials with special geometry drills

The cutting tool geometry is strongly influencing damage induced during drilling of composite materials. The searching of new and optimum geometries reducing the damage on the laminates is still a challenge for the scientific community and industry. This study focuses on drilling woven CFRP laminates with four different tool geometries, analyzing the influence of the cutting parameters on the cutting forces and delamination damage. The work is divided in three phases; the first phase carries out a full factorial design of experiments conducted to quantify the significance of each process parameter as well as its interaction, on the generation of delamination at the hole entry and exit as well as the thrust force and torque. The second phase uses the response surface methodology (RSM) to establish the relationships between each output variable and the input variables based on ANOVA results. Finally, a multi-objective optimization strategy has been presented using the fitting equations to select optimum ranges of design parameters that can minimize collectively the aforementioned output variables. Ultimate objective is the process improvement toward negligible defects during drilling of woven CFRP composites.

Dedicated drill design for reduction in burr and delamination during the drilling of composite materials

In the drilling of composite materials such as carbon fiber reinforced plastic, burrs and delamination occur during machining. This study proposed a design of a drill tool with a shape that suppresses burrs and delamination during the drilling of composite materials. The tool shape (tip, groove, land, etc.) is determined, and a nick shape that cuts off chips and reduces heat generation is adopted. A finite element analysis and an experimental evaluation involving 4600 holes were conducted. The maximum errors in the hole diameter and roundness were 15 μm and 0.016, respectively. Further, the maximum burr height was observed to be 80 μm or less, and delamination was not observed in the experiment.

Assay of Machining attributes in Drilling of Natural Hybrid Fiber Reinforced Polymer Composite

In the accelerated competitive manufacturing world, the vital objectives of the manufacturer are to generate high quality products at least cost and in fewer time. The utilization of composite materials is mounting at a fast rate, because these materials have many constituents and each has its own unique characteristics like environment friendliness and light weight, with high precise properties. The above requirements are inculcated by incorporating the natural fibers namely kenaf, sisal and aloe vera fibers as reinforcing material in the polymer resin matrix in hybrid manner. The drilling of composite materials is intricate when compared to metals, because the tool has to go by the matrix and reinforcement alternately, which have dissimilar properties. The aspiration of this work is to highlight the drilling characteristics of four different types of fiber plates namely polyvinyl chloride reinforced hybrid composite, polyvinyl chloride reinforced hybrid with boron carbide compound, vinyl ester reinforced hybrid composite and vinyl ester reinforced hybrid with boron carbide composite by varying the cutting speed and feed rate.The drilling process is carried out on a radial drilling machine using HSS drill.The fabricated composites are subjected to drilling in order to identify the extent of delamination. The delamination in drilling is higher for the poly vinyl chloride polymer when compared to vinyl ester polymer, showing that vinyl ester is better suited as resin for the hybrid (kenaf, sisal, aloe vera) fibers. The study of thrust force, torque, and temperature developed during drilling reveals that HSS is better suited to drill vinyl ester reinforced with hybrid fiber at lower speed.

Drilling simulation of Fibrous Composites: Technical Note

Drilling of composite material is more complex than conventional drilling, as material removal of isotropic material is uniform than composite material. The cutting edge of drill bit will damage the composite material and removes the fibre in indefinite manner. Improper holes in composite material will cause improper assembly and even can cause premature failure of components made with composite material such as CFRP, Carbon fibre, glass epoxy. By estimating optimal machining parameter such as Feed rate and cutting speed, machining of improper holes in composite material can be eliminated. Optimal machining parameter can be estimated by simulation of composite material. Simulation is performed with help of Abaqus/Explicit software from Simulia

A novel variable-dimensional vibration-assisted actuator for drilling CFRP

Comparing to the conventional drilling (CD), vibration-assisted drilling (VAD) is a novel machining technique suitable for drilling in hard-to-machine materials such as carbon fiber-reinforced polymer (CFRP). However, the current VAD apparatuses are limit in the following vibration modes: one-dimensional longitude vibration and two-dimensional elliptic vibration, which both have the flaws for drilling in CFRP. In order to improve the VAD’s performance in the CFRP drilling, a novel variable-dimensional vibration-assisted drilling (VDVA) actuator is proposed, which can produce one-dimensional longitude vibration, two-dimensional elliptic vibration, and three-dimensional composite vibration, to adapt different machining phase in drilling FRP. One-dimensional longitude, three-dimensional composite, and two-dimensional elliptic vibration can be used in the entrance, middle, and export separately, which can improve drilling precision, chip capacity, and aperture accuracy and reduce the delamination and burr phenomena. Firstly, based on process requirements of drilling FRP, an actuator design method including piezoelectric transducer and horn design is proposed to establish the actuator model, which can be used to generate variable-dimensional vibration. Then, the system control for the proposed actuator is designed to output different vibration mode in actual drilling process. The resonant frequency and amplification ratios of the proposed actuator are analyzed by using FEA software. Based on the above analysis results, a prototype of the proposed actuator is fabricated, and then its vibration characteristics are evaluated by a micro-displacement sensor. With different phase sinusoidal driving voltages at different frequency of 20.7 and 5.8 kHz, the developed prototype achieved variable-dimensional vibration with one-dimensional longitude vibration of amplitude 11.0 μm, two-dimensional elliptic vibration of amplitudes 13.0 and 12.0 μm, and three-dimensional composite vibration of amplitudes 7.0, 10.8, and 12.1 μm. The experiments indicate that the performance of the developed actuator is satisfied, and the proposed actuator can be applied in composite material drilling process to improve the machining performance of composite material.

Special Issue on Service Engineering

To solve problems underlying design and manufacturing we often rely on methodologies of computational intelligence such as machine learning, artificial neural networks, fuzzy logic, fuzzy inference systems and smart optimization algorithms. In this Special Issue of the International Journal of Automation Technology, original articles are presented with reference to the engagement of intelligent computation in diverse application areas of design and manufacturing, including manufacturing process monitoring, manufacturing systems management, scheduling, design theory and methodology. The six research papers in this Special Issue propose the use of intelligent computation methodologies to deal with various topics related to manufacturing and design. In particular, the first three papers focus on manufacturing process monitoring with reference to different manufacturing technologies, including tool wear monitoring in drilling of composite materials, sensor monitoring in CNC turning and residual stress prediction in welding. Diverse intelligent approaches such as artificial neural networks and adaptive neuro-fuzzy inference systems are proposed to support manufacturing process monitoring. The fourth paper deals with the manufacturing system level, proposing the employment of a solution algorithm combining metaheuristics and operation simulation for scheduling of production processes. The fifth paper aims at developing tools to guide the manufacturers to manage the technology investment and cost saving target for customer satisfaction based on the application of internet of things. The last paper proposes a methodology to support the introduction of customer requirements in product and service design via a decision support system which exploits artificial intelligence algorithms (machine learning) based on inductive inference, allowing knowledge related to product/service to be mapped, structured and managed to design the service and product semantic model. The editors deeply appreciate all the authors and anonymous reviewers for their effort and excellent work to make this Special Issue unique. We hope that future research on intelligent computation in manufacturing and design will advance manufacturing technology and systems as well as design methodologies.

Special Issue on Intelligent Computation in Design and Manufacturing

To solve problems underlying design and manufacturing we often rely on methodologies of computational intelligence such as machine learning, artificial neural networks, fuzzy logic, fuzzy inference systems and smart optimization algorithms. In this Special Issue of the International Journal of Automation Technology, original articles are presented with reference to the engagement of intelligent computation in diverse application areas of design and manufacturing, including manufacturing process monitoring, manufacturing systems management, scheduling, design theory and methodology. The six research papers in this Special Issue propose the use of intelligent computation methodologies to deal with various topics related to manufacturing and design. In particular, the first three papers focus on manufacturing process monitoring with reference to different manufacturing technologies, including tool wear monitoring in drilling of composite materials, sensor monitoring in CNC turning and residual stress prediction in welding. Diverse intelligent approaches such as artificial neural networks and adaptive neuro-fuzzy inference systems are proposed to support manufacturing process monitoring. The fourth paper deals with the manufacturing system level, proposing the employment of a solution algorithm combining metaheuristics and operation simulation for scheduling of production processes. The fifth paper aims at developing tools to guide the manufacturers to manage the technology investment and cost saving target for customer satisfaction based on the application of internet of things. The last paper proposes a methodology to support the introduction of customer requirements in product and service design via a decision support system which exploits artificial intelligence algorithms (machine learning) based on inductive inference, allowing knowledge related to product/service to be mapped, structured and managed to design the service and product semantic model. The editors deeply appreciate all the authors and anonymous reviewers for their effort and excellent work to make this Special Issue unique. We hope that future research on intelligent computation in manufacturing and design will advance manufacturing technology and systems as well as design methodologies.

Analytical Prediction of Delamination during Drilling Composite Laminates

Drilling of composite material is a widely used operation in the aerospace industry. Despite of all precautions during the drilling process, the exit-ply delamination is still one of the major problems that affect the integrity and service life of the parts. The exit-ply delamination is directly related to the mechanical properties of composite materials as well as the nature of the induced thrust force along the cutting and chisel edges. In the current study, an attempt is made to model the induced thrust force. Both point and linear distributed loads models were utilized with consideration of elliptical delamination area. In order to validate the proposed model, a comparison between previous analytical models, measured forces, and the current proposed model is presented and discussed. The presented work was based on two scenarios. The first scenario considers the first mode of fracture only, while the second scenario considers the mixed- fracture mode criterion. The 1st scenario offers an average model accuracy about 77.9%, while the 2nd scenario offers an accuracy about 94.7% when compared to the predicted and measured data. It must be stated that both scenarios offer better prediction when compared to available model in the open literature. Thus, it can be concluded that the proposed model effectively demonstrates the delamination behaviour when drilling laminate composites.

The effect of support on multi-hole drilling for glass fiber-reinforced plastic composite materials

Mechanical joint of fastener is widely used in the assembling and repairing of the modern aircraft composite components, so multi-row holes are needed in jointing, and their quality directly influences the reliability of aircraft structures. So, multi-hole drilling of composite components becomes one of important processes. A large number of researchers have carried on the detailed and thorough research for the drilling process and corresponding damage based on single-hole drilling of composite materials, but none corresponding research was based on multi-hole drilling of composite materials. In the case of a round-hole array backing plate and a square-hollow backing plate as supporting, this paper carried out finite element simulation, theoretical analysis, and experimental research for multi-hole drilling of glass fiber-reinforced plastic (GFRP) composite materials. The study aimed at contrasting and analyzing S33 stresses, thrust forces, and exit delamination damage of multi-hole drilling between the two kinds of support cases and between the internal of each support case. The results showed that S33 stresses, thrust forces, and exit delamination damage existed significant difference between two kinds of support cases. What is more, S33 stresses, thrust forces, and exit delamination damage have no difference with a round-hole array backing plate as supporting; under a square-hollow backing plate as a support, S33 stresses, thrust forces, and exit delamination damage existed significant difference with the changing of straight-line distances from the center of hole to the center of backing framework. On the basis of this study, the analytical results provided corresponding theoretical guidance for the multi-hole drilling in the assembling and repairing for the composite components.