High-speed Steel Drill Research Articles

Surface modification of high-speed steel (HSS) drills by plasma nitriding and cathodic cage tin deposition

Cutting tools made of high-speed steel have significant economic and technological importance. To enhance their productivity, thermochemical treatments are sought to improve both surface mechanical and tribological properties. Plasma nitriding and thin film deposition are widely employed for this purpose. In this study, modifications were made to M2 high-speed steel drills through plasma nitriding at temperatures of 400°C and 450°C. Cathodic cage TiN plasma deposition was also performed, varying the dwell time at a fixed temperature of 450°C. Characterization techniques included optical microscopy, X-ray diffraction (XRD), Vickers microhardness testing, and scanning electron microscopy (SEM). Performance tests were carried out to evaluate the behavior of the drills in relation to wear when machining AISI 1020 steel. It was observed that longer deposition times promote more uniform and thicker layers, and higher nitriding temperatures result in thicker nitride layers. An increase in hardness was noticeable in all deposition and nitriding treatments, with the nitrided samples exhibiting the highest hardness. During performance tests, the cathodic cage plasma TiN deposition demonstrated greater potential for application in HSS drills, with a treatment lasting 4 h providing the best results.

Investigating the impact of drill material on hole quality in jute/palm fiber reinforced hybrid composite drilling with uncertainty analysis

This study presents a method for modelling, predicting, and evaluating the impact of drill materials on the drilling process of hybrid palm/jute polyester composites, with the aim of enhancing hole quality regarding delamination, circularity, and cylindricity. Three drill materials, including High-Speed Steel (HSS), 5 % Cobalt-coated High-Speed Steel (HSS-Co5), and Solid Carbide drills were tested, and their impacts on drilling performance were assessed. Through thorough experimentation and statistical analysis, significant differences in results were observed between HSS drills and both HSS-Co5 and Solid Carbide drills. However, the variation in results between HSS-Co5 and Solid Carbide drill results was minimal. Additionally, the findings highlight notable disparities among drill types concerning uncertainty. The results also indicate that feed rate, drill material, and their interaction play crucial roles in determining drilling efficiency. Specifically, HSS drills consistently outperformed HSS-Co5 and Solid carbide drills, demonstrating superior performance in minimizing delamination, improving circularity, and enhancing cylindricity along with lower uncertainty.

Research on the Application of Superhard Coating Technology for Cutting Tools in Mechanical Processing

The superhard coating technology for cutting tools has important applications in the field of mechanical processing. This article introduces the development of superhard coating materials for cutting tools, including low-pressure gas-phase synthesis of diamond, cubic boron nitride, and physical vapor deposition (PVD) coating technology. The superhard coating of cutting tools is widely used in turning, milling, tapping, key component machining, high-speed steel drill bits and taps. Research has shown that coatings can reduce cutting forces and improve tool life, but attention should be paid to residual compressive stress. The future development direction includes researching new superhard material cutting tools and developing coating methods that are more wear-resistant and have high temperature hardness.

An Analysis of Chip Formation and Hole Circularity in Drilling Applications: An Aircraft Components Perspective

Drilling plays a critical role in the production of precise holes for aircraft components. However, drilling aluminum alloys poses challenges, leading to poor hole quality and potential defects in the airframe structure. This study focused on investigating chip formation, hole circularity, and drilling parameters, specifically feed rate and spindle speed. Dry drilling trials are conducted using high-speed steel drill bits and the Al6061-T6 alloy. The CIMCO MDC-MAX software is employed to monitor machine performance and accumulate comprehensive data. The study investigates the effect of varying feed rates on hole circularity, chip development, and chip thickness. Findings indicate that higher feed rates result in increased circularity error and chip thickness. The circularity graph shows inconsistencies due to workpiece vibration during drilling. Chip thickness rises with the feed rate, particularly with an increased number of drilled holes, attributed to factors such as tool rubbing and improper cutting. Additionally, the study highlights the correlation between machine performance and product quality. The CIMCO MDC-MAX data reveals that a feed rate of 0.260 mm/rev corresponds to high machine performance and low circularity. Conversely, Drill 6, operating at a feed rate of 0.230 mm/rev, exhibits poor machine performance and higher average circularity. The research enhances understanding of chip formation and hole circularity in drilling applications for aircraft components. The results emphasize the importance of optimizing drilling parameters to achieve superior hole quality. Practical implications are provided for enhancing the drilling process in aerospace manufacturing.

Deform 3D Simulation and Experimental Study in Machining of AISI 1020 Mild Steel

The drilling process plays a crucial role in the assembly process of modern-day manufactories. One of the major causes of component rejection during drilling operations is the incorrect selection of spindle speed and feed rate. Therefore, this study aimed to investigate the impact of process factors such as spindle speed and feed rate on torque, thrust force, temperature surface roughness, and chip formation during the drilling of AISI 1020 mild steel. A combination of finite element modeling and experimental investigation was employed to achieve the process. Specifically, the commercially available finite element software, Deform 3D, was used for simulation. The modeling results were then compared and validated with the experimental data. A high-speed steel drill bit was utilized during the modeling and experimentation. The spindle speed was varied at 330, 410, and 510 rpm, while the feed rates were set at 0.12, 0.2, and 0.3 mm/rev. The study’s findings suggest that the spindle speed has an inverse relationship with thrust force, torque, and surface roughness, whereas it has a direct relationship with temperature. Conversely, the feed rate directly correlates with thrust force, torque, temperature, and surface roughness. Additionally, an analysis of the chips produced during the experiments revealed the impact of the cutting conditions on chip formation. The study results showed a 2–10% discrepancy between the experimental and simulation data. The ANOVA results indicated that the feed rate contributes the most to thrust force and torque, with a percentage contribution of 61.73% and 59.87%, respectively, followed by spindle speed, with a percentage contribution of 37.09% and 38.89%, respectively. Furthermore, temperature influences spindle speed the most, followed by feed rate, with percentage contributions of 67.75% and 31.11%, respectively. Moreover, the feed rate’s percentage contribution to surface roughness is higher than the spindle speed, with a contribution of 66.20% and 32.18%, respectively.

Evaluation of the drilling process in 6061-T6 Al-Mg-Si alloys using AISI M-35 diamond-like carbon coated high-speed steel drill

The diverse mechanical properties found in aluminum alloys make them an ideal option for various industrial sectors. The machining process still presents challenges, especially adhesion. The common way to deal with high machining temperatures is to use cutting fluid. However, due to environmental and operator health issues, alternatives to these products have been sought. One possibility to reduce these problems is by using film-coated tools such as Diamond-Like Carbon (DLC), which provides high hardness and a low coefficient of friction, and whose good performance is related to its adhesion on the tool surface. The present work investigated the performance of ground high-speed steel drills coated with DLC in the drilling process of 6061-T6 Al-Mg-Si alloy. Furthermore, the material was characterized and an analysis of the macro and microgeometric errors of the alloy was carried out. The results obtained from the analysis of the machined alloy were, for the most part, uniform. An increase in tool life was observed, which was able to machine 1000 dry holes.

An Application of Data Envelopment Analysis in the Selection of the Best Response for the Drilling of Carbon Fiber-reinforced Plastic Composites

In the drilling operation, defects such as delamination at exit and entry are very disturbing responses that impact the efficiency of the drilling process. Without control, an exponential growth in the amount of drilled components with defect quantities may result. Thus, the process engineer has input in attaining the desired production levels for components in the drilling process. Consequently, this article deploys a novel method of data envelopment analysis to evaluate the relative efficiency of the drilling process in reducing the defects possible in the producing components from the CFRP composites. The high-speed steel drill bits were utilized to process the CFPs, while the responses considered are the entry and exit determination, thrust force, and torque, among others. Literature experimental data in twenty-seven experimental counts were summarized into fewer groups and processed through the data envelopment analysis method. The results show that capturing the CFRP composite responses is feasible, providing an opportunity for enhanced efficiency and a situation where undesirable defects in the CFRP composite production process may be eradicated. The article’s uniqueness and primary value are in being the foremost article in offering an updated vast representation of the comparative efficiency of CFRP composite parameters within the literature for the composite area. The work adds value to the CFRP composite literature by envisaging and understanding the comparative efficiency for the parameters, identifying and separating the best from the worst decision-making unit. It also reveals how the parameters are linked by their relative placements. The article's novelty is that using data envelopment to compare the efficiency in reducing drilling defects such as entry and exit determination, among others. The method’s utility is to provide information for cost-effective drilling operations during the planning and control phases of the operation.

Research solution for automatic hole quality analysis when drilling fiber-reinforced composites

Fiber-reinforced polymers are highly demanding composites in aerospace and automotive areas because of their excellent mechanical properties such as stiffness and strength-to-weight ratio. The drilling remains the major machining operation applied to composites to provide high-quality holes for joints between parts. Due to composites plied structure, the drilling is accompanied with unusual form metal cutting defects such as delamination and uncut fibers around the drilled hole. Considering that the tool life of some drills reaches over thousands of holes, the research of composites machinability becomes difficult due to demanded labor intensity in manual inspection of the hole quality. Therefore, this paper develops the research solution for automatic analysis of the hole quality in drilled fiber-reinforced materials. The paper proposes a complex of solutions aimed to speed up the analysis of the hole quality when composites drilling. The solution consists of the developed vacuum table, robot arm with high-speed camera, developed top and bottom lightning systems, and Image Processing algorithms for defect detection from captured images. The paper results show how the developed solution can be used for high routine research activities. The output data, including tested 72 cutting data parameters and full-size tool life test, allowed identifying the operational window for high-speed steel drills and the range of tool life, where drill ensures a certain hole quality. The paper shows the efficiency of the developed research solution can reach 5 s per hole including drilling and full cycle of measurements having measurement error of 1–3%.

Machining of aluminium 6063 alloy using high strength steel and titanium nitride novel coated drill tool using CNC and comparing the material removal rate

This study compares two tools, HSS M42 and TiN Coated twist drill bits, in order to determine which tool has the better material removal rate (MRR). Drill bits were of high speed steel (HSS M42) tool and use of Novel coating of Titanium Nitride on HSS tool in this study. The machining is done on a experimental specimen made of aluminium alloy AA6063. The material removal rate of both tools is measured in CNC drilling on two sets of 20 specimens each. Spindle speed, depth of cut, and feed were all controlled variables. G power 80% used for calculating sample size. SPSS software was used to record and analyse the results for both tools. The average MRR recorded for HSS M42 tool was 14.9803 mm3/s with a Standard deviation value 1.713221. This study has a significance value of 0.037 (p < 0.05) with a g power of 80%. The titanium nitride coated tool had an average MRR of 20.06995 mm3/s and 1.179870 standard deviation. The results were achieved at 0.037 significance, that is lower than 0.05. The titanium nitride coated drill bit has comparatively better MRR than the high speed steel drill bit in no-lubricant and no-coolant drilling circumstances, as per this study.

STUDY THE EFFECTS OF THE MULTINITE COAT OF THE HIGH SPEED STEEL DRILL BIT IN DRILLING

Drilling is an important metal manufacturing processes. Drill bits are used in drilling to create holes. Wear of drill bits can have an adverse effect on the quality of the drilling hole. To increase the wear resistance of drill bits, surface modifications have been introduced and studied their effectiveness. Multinite coating is a candidate for surface modification techniques to increase wear resistance of the drill bits. In this study, the effect of multinite coating on the wear resistance of drill bits has been investigated. Two types of 6 mm diameters drill bits, the uncoated high speed steel, and the multinite coated high speed steel drill bits, were used to create the hole with 30 mm in depth on ASTM A36 steel. The drilling parameters were 1,100 rpm of rotation speed and 135 mm/min of the feed rate. The thrust force and the cutting torque during drilling were measured by a force sensor. Flank wear on the drill bits were measured by overlap image technique. Also, the roughness of hole surfaces were investigated. Results showed that the higher surface hardness of multinite coated high speed steel drill bit led to a lower flank wear rate at the beginning of drilling. Consequently, built-up of chip on the multinite coated high speed steel drill bit was less compared to the uncoated one. We conclude that the higher surface hardness of multinite coated high speed steel drill bit improves the wear resistance of drill bit by a decrease of wear rate at the beginning of drilling and a lesser amount of chip built-up on the cutting edge and the surface quality of hole after drilling.

Optimization of Drilling Parameters in Sisal-Human Hair Hybrid Composite Using Grey Relational Analysis

Sisal is the most commonly used natural fiber in polymer composites due to its high strength, durability, and ability to stretch. In this present work, sisal and human hair were used as reinforcement for epoxy resin-based hybrid composites, and their effect on the mechanical properties was reported. Four composite plates with fiber volume fractions of 10%, 20%, 30%, and 40% were fabricated by the hand lay-up method. Chopped sisal fiber and human hair of 30 mm length were mixed with epoxy resin to fabricate the composites. In addition, high-speed steel (HSS) drills were used to study the influence of drilling parameters such as speed, feed, and drill point angle on the quality of the drilling. Three factors with three levels were considered for the design of the experiment. The drilling parameters were optimized using Grey Relational Analysis and the Taguchi method for the reduction of delamination. The experimental results indicate that a flexural strength of 38 MPa was achieved in a 60% epoxy, 20% sisal, and 20% human hair composite. NI vision assistant software was used to process the images taken on the drilled holes using the Matrix Vision camera. The optimization results showed that the feed rate played a pivotal role in deciding the delamination on the entry side of the hole. In contrast, the drill point angle significantly affects the delamination at the exit side of the hole. Better quality holes are achieved with a cutting speed of 2500 rpm and a feed rate of 50 m/min.

Evaluation of delamination in drilling of SiCp/sisal fiber reinforced epoxy composites by the analysis of acoustic emission and cutting force: Influence of tool condition

The presence of SiC particulate in the newly developed SiCp/sisal fiber/epoxy composites on drilling, influence the wear in the drill bit. This article presents the experimental investigations of the effect of tool condition on delamination during drilling of composite by the time, frequency domain, and discrete wavelet packet transformation (DWPT) of acoustic emission and cutting force measured in process. It may further be helpful for determining and assessing the root cause of the induced delamination damage. The drill bits are made of high-speed steel (HSS), the condition is categorized into three different types namely as received, cryogenically treated (−80°C for 24 h), and cryogenically treated and tempered (−80°C for 24 h and 200°C for 2 h). Study of the frequency domain reveals that the dominant frequency of the acoustic emission (AE) signals falls between 100 and 300 kHz. The AE-specific energies of the decomposed signals are calculated based on DWPT analysis. It is noted from the AE specific energy that shearing occurs during drilling process. The cryogenically treated and tempered HSS drill contributes significantly to the reduction in delamination compared to other tools employed in this investigation.

Analysis of the Effect of Tool Geometry and Hole Quality on Drilling Carbon-Fibre Reinforced Polymer Composite Using ANSYS

This study focused on the analysis of the effect of tool geometry and hole quality on drilling carbon-fibre reinforced polymer (CFRP) composite using ANSYS. The experiment was conducted on computer numerical control machine (CNC) using high speed steel (HSS) twist drill bit and HSS-COBALT drill type. Taguchi L9 orthogonal array was used for the optimization analysis. Analysis of variance (ANOVA) was employed to determine the most significant control factors affecting the drilling process. The machining parameters involving tool type, point angle, spindle speed and feed rate were selected as control factors. While the dependable variables on workpiece were cutting force, stress and strain. The main interaction effect of the input variables on the predicted responses was investigated. The ANOVA/F-test results for cutting force with the contribution of each machining parameters revealed that the cutting speed was the dominant factor influencing cutting force developed with a contribution of 57 percent, The second factor affecting cutting force developed was point angle with a contribution of 5.7 percent, while f eed rate had the least effect on cutting force developed where its contribution of 1.4 percent. Based on the results observed, the optimal machining parameters that produced minimum stress was observed with HSSCOBALT drill at 118 degrees of point angle, 300 mm/min of feed and 500 rpm of speed. Also from Taguchi results, the optimal combination of process parameters to obtain maximum strain with HSS drill, 135 degrees of point angle, and 300 mm/min of feed and 1500 rpm of speed produced the optimal drilling condition for CFRC polymer within the scope of this research work.

Effect of Nitrogen Ion Implantation on the Tool Life Used in Particleboard CNC Drilling.

The paper presents the effect of nitrogen ion implantation on the tool life of the tools commonly used in the furniture industry for drilling particleboards. Nitrogen ions with different accelerating voltages of 25, 40, 55, and 70 kV and a fluence of 5 × 1017 cm−2 were implanted into the surface of commercially available high-speed steel (HSS) drills, using the implanters without mass-separated ion beams. The tests were carried out in a computerized numerical control (CNC) machining center used in the furniture industry. Based on the measurements of the direct tool wear indicator (W), the drill wear curves were determined and the relative tool life index, standard deviation, coefficient of variation, and the implantation quality index of tool life were calculated. The studies have shown that the modification of the drill surface layer by the nitrogen ion implantation process increases the tool life. The obtained results allow the research to be the continued in a wider scope.

Multi response optimization of machining parameters for an annealed Monel K 500 alloy in drilling using Machine learning techniques and ANN

Manufacturing companies are focusing on continuous process development to thrive in today’s quality-conscious market. It is particularly relevant to investigate machining processes for advanced materials such as superalloys. Drilling is a major operation that is used in the majority of manufacturing processes. Hence, this research work is focused on investigating the drilling performance of the Monel K500. The output responses under consideration are metal removal rate (MRR), surface roughness, and tool wear. Various contemporary techniques were utilized in this work, namely machine learning methods, artificial neural networks, principal component analysis, and grey relation analysis using uncoated, coated, and HSS (high-speed steel) drills. After annealing, the softened material can be easily machined to increase the MRR and decrease tool wear and surface roughness. The experimental results show that, after annealing, the surface roughness values for HSS drills have been reduced by 23.86%, uncoated drills by 27.29%, and coated drills by 29.27%, respectively. Moreover, tool wear values for HSS drills decreased by 28.51%, uncoated drills by 34.7%, and coated drills by 33.71%, based on the relative error approach. MRR values for HSS drills increased by 20.51 %, uncoated drills by 23.08%, and coated drills by 23.5%, respectively. For PCA (principal component analysis), feed (47%), and for GRA (gray relation analysis), feed (40.1%) will be the significant parameter followed by speed, and both methods have identified the same experimental run values for optimization of cutting parameters. The theoretical values were predicted using machine learning methods, which utilized the Python language using the Google Colab and then validated with experimental values. The predicted values obtained by the decision tree are close to the measured values as compared to support vector regression and K-nearest neighbor based on relative error. The estimated values obtained by the ANN (artificial neural networks) approach, using Easy NN plus software, match well with the actual values, with a slight deviation.

Redeposition layer formation caused by shading effect during sputter cleaning and associated damage on rake face of TiN coated high-speed steel drills

The degradation of protective hard coatings has a detrimental influence on the performance of metalworking tools like universal drills. Not only do the chemistry and structure of the coating have an influence on the tool damage behavior, but also the tool production steps can cause coating/substrate interface artifacts which weaken the adhesion of the coating to the tool surface. As the current paper will show, the given cutting edge geometry of a drilling tool made of high-speed steel (HSS) caused diminished visibility of the rake face and is referred to as shading. The shading of the rake face caused numerous artifacts, which negatively affected the wear behavior of the tool and the titanium nitride (TiN) coating. Examples of artifacts were (i) different surface roughness for flank and rake face, (ii) burr formation on the rake face, (iii) decreasing coating thickness from flank to rake face, and (iv) a redeposition layer of sputtered material on the rake face. This paper is focused on the failure behavior of a redeposition layer. The layer's occurrence was caused by the redeposition of sputtered substrate material during the sputter cleaning with Ti+ ions and was mainly limited to the area near the cutting edge. An additional local influence through the given rake surface waviness was present. The redeposition layer was an indication of an insufficient sputter cleaning process, whereby chromium oxides remained on the matrix surface. As a result, the layer adhesion of the given TiN/HSS system was lowered significantly, and delamination occurred at the rake face near the cutting edge. This led to increased overall wear velocity and diminished tool lifetime.

Cutting forces during drilling of a SiCp reinforced Al-7075 matrix composite

Abstract In this study, an Al-7075 matrix alloy reinforced and by 5, 10, and 15 wt% silicon carbides were produced as a composite material using the stir casting method. An investigation of the hardness, density, and microstructure of the matrix alloy and the composite materials was conducted. The following instruments were used for the microstructure studies: optical microscope and scanning electron microscope (SEM). The machinability behavior of the produced composite materials was investigated by using the drilling method with a three-axis computer numerical controlled (CNC) milling center. High-speed steel (HSS) and titanium nitride (TN)-coated HSS drill bits were used in the machinability tests. As drilling process cutting conditions three different feed rates (FRs) of 0.05, 0.10, and 0.15 mm·rev−1 and three different cutting velocities (CVs) 15, 20, and 25 m·min−1 were applied. The effects of cutting conditions such as FR, CV, reinforcement phase ratio, and cutting tool type on cutting forces such as thrust force (TF) and torque (TQ) in the drilling process were studied in detail. According to the experimental results, TF and TQ decreased with the increase in the CV and increased with the increase in the FR.

The influence of tool quality on the machining of additive manufactured and powder metallurgy titanium alloys.

This study was carried out to investigate the impact the quality of the drill bits has on the machining behavior of additive manufacturing (AM) and powder metallurgy (PM) titanium alloys. Therefore, commercially available drill bits which typically reflect two extremes of drill bit quality were selected. The performance of coated carbide twist drills, typically recommended for the drilling of wrought titanium alloys was compared with that of high-speed steel (HSS) drills. The average torque value, specific cutting energy (SCE), and tool wear were used to evaluate the drilling performance of AM and PM titanium alloys. The results of drilling tests revealed the application of the coated carbide drill resulted in lower torque and SCE values, less flank wear, and lower build-up-edge (BUE) compared with the uncoated HSS drill bits for AM fabricated titanium alloys. However, the carbide drill appeared to offer negligible improvement over the uncoated HSS drill when employed with the PM fabricated titanium alloy. In spite of the improvement in the drilling performance offered by the carbide drills for the AM titanium alloy, TiB intermetallic particles (part of the AM titanium microstructure) contributed to the damage of the coated carbide drill which would limit the drill lifetime.

Performance of High-Speed Steel Drills in Wet Drilling Inconel 718 Superalloy

Performance of High-Speed Steel Drills in Wet Drilling Inconel 718 Superalloy

Tool wear and burr formation during drilling of aluminum alloy 7075 in dry and with cutting fluid

Aluminum alloy 7075 (Al 7075) has been widely used in aerospace and automotive industries to replace heavier alloys. This is because of its superior properties of high specific strength, high corrosion resistance, good formability, recyclability and low fabrication cost. However, the ductility and heat generation during drilling Al 7075 often produces a burr at the entrance and exit of the workpiece surface. This research investigates the effect of cutting speeds and drilling conditions on the burr formation of Al 7075. Drilling was performed in dry and with conventional cutting fluid using 6.0 mm high speed steel drills with cutting speeds of 22, 44 and 66 m/min at a constant feed rate of 0.15 mm/rev. The use of cutting fluid in drilling Al 7075 caused lower tool wear by 42%, 38% and 30%, respectively, at 22, 44 and 66 m/min, compared to dry drilling. As for burr formation, drilling with cutting fluid on average resulted in 20% lower burr root width and 10% lower burr height than dry drilling for all cutting speeds. This study indicated that drilling Al 7075 using the cutting speed of 44 m/min with cutting fluid is beneficial as it resulted in the least tool wear and minimum burr formation.