Carbide End Mill Cutter Research Articles

Development of an EN8 Steel Stepped Rotor by a Novel Engraving Milling Technique.

The rotor or impeller is a rotational and key part of a pump and compressor. This article presents the detailed development process of a rotor of small size constructed from an EN8 steel cylindrical blank using a novel technique based on a computer numerical control engraving milling machine (CNC-EMM) equipped with a 4 mm tungsten carbide end mill cutter. We fabricated a total of twenty-eight stepped rotors following the Box-Behnken Design (BBD) DoE technique at fourteen distinct combinations of CNC-EMM variable parameters, namely rotational speed, feed, and plunge feed. Average roughness 'Ra', an important surface quality indicator, has been considered and presented in this article, as a quality measure for the fabricated rotors. Feed and plunge feed have been identified as the most influencing variable parameters as per an analysis of variance (ANOVA) test. The lowest average roughness value obtained by this process for the rotor blade was 0.11 µm. A micrograph obtained from a field-emission scanning electron microscope (FE-SEM) showed a uniform and accurate tooth profile along with burr formation at corner edges. This study claims to establish engraving milling as a viable alternative to other manufacturing processes used for rotor blades. The findings of this study are useful to scholars, engineers, and researchers who are exploring new ways to fabricate mechanical parts and components.

Sharpening of graded diamond grinding wheels

Grinding the flutes of cemented carbide end mill cutters results in high and uneven radial wear of the grinding wheel. This is a consequence of the varying geometrical contact conditions over the grinding wheel width. Decreased manufacturing accuracy regarding the tool target geometry is the consequence. To compensate for this, the dressing intervals must be shortened. High non-productive times and an additionally reduction of the grinding layer results from this. The higher non-productive times reduce the productivity of the grinding process and, in conjunction with the shorter lifetime of the grinding tool, thus increase the costs per work piece. It has already been shown that load-adapted grinding wheels can reduce uneven radial wear up to 50%. The adaptation of the wear behaviour to non-uniform engagement conditions causes non-uniform radial wear to occur again under uniform engagement conditions. Uniform engagement conditions occur during grinding wheel sharpening. Therefore, the present study investigates the influence of sharpening on the grinding tool topography. For this purpose, sharpening tests are carried out on four differently graded grinding wheels. For comparability, the tests are also carried out on two non-graded grinding wheels. In the present work, the surface parameters are evaluated with regard to their suitability for analysing the sharpening condition of graded grinding wheels. The grain protrusion derived from this is subsequently used for evaluation. For this, a dependency on the grain concentration is proven and the grain protrusions are shown over the grinding wheel widths. From this, sharpening parameters are determined that enable reproducible sharpening of graded grinding wheels.

High-Speed Machining of Ti–6Al–4V: RSM-GA based Optimization of Surface Roughness and MRR

This article offers experimental research into getting the lowest possible roughness on the surface profile of Ti–6Al–4V produced by High-Speed Machining (HSM) in conjunction with the highest feasible material removal rate (MRR). All three machining variables—cutting speed (mm/min), feed rate (mm/min), and depth of cut (μm)—are investigated in this experiment. The combined optimization of Response Surface Methodology (RSM) and Genetic Algorithm (GA) are used to optimize the cutting parameters for a high-speed end milling operation. For the 20 distinct runs that CCD (Central Composite Designs) offers, employing uncoated cemented carbide end mill cutters is a more affordable choice for cutting the alloy Ti–6Al–4V. Machining data are analyzed with Design Expert software and MATLAB, respectively, utilizing RSM and GA. It has been shown that speeding up the cutting speed (105.56–138.86 mm/min) while decreasing the feed rates (25–37 mm/min) improves surface roughness. The minimum achievable surface roughness predicted by GA and RSM are 0.063 μm and 0.093 μm, respectively. This study presents that the desirability of getting the optimum result would reduce sharply (26.39%) by sacrificing the surface roughness for only 0.1 μm. The cutting edge will be ready for machining with optimum machining combination (cutting speeds of 105.56 and 138.86 m/min and feed rates of 25 and 37 mm/min). The findings illustrate that lowering the surface roughness by only 0.1 μm will increase the MRR rapidly (50.83%). A comparative study on the MRR is also conducted within the investigated input parameters range. The morphology of tool wear and the texture of the machined surface are examined using scanning electron microscopy (SEM) pictures.

Tool Condition Monitoring Using Machine Tool Spindle Electric Current and Multiscale Analysis while Milling Steel Alloy

In the metal cutting process, the tool condition directly affects the quality of the machined component. To control the quality of the cutting tool and avoid equipment downtime, it is essential to monitor its condition during the machining process. The primary purpose is to send a warning before tool wear reaches a certain level, which could influence product quality. In this paper, tool condition is monitored using fractal analysis of the spindle electric current signal. The current study analyzes the monitoring of the cutting tool when milling AISI 5140 steel with a four-flute solid carbide end mill cutter to develop monitoring techniques for wear classification of metal cutting processes. The spindle electric current signal is acquired using the machine tool internal sensor, which meets industrial constraints in their operating conditions. As a new approach, the fractal theory is referred to analyze the spindle electric current signal and then assess the tool wear condition during the metal cutting process. Fractal parameters were defined to extract significant characteristic features of the signal. This research provides a proof of concept for the use of fractal analysis as a decision-making strategy in monitoring tool condition.

Effect of end milling parameters on MRR and hardness variation of AA7075

The end milling process is a bulk machining process used for machining an edge surface on the part, making slots, pockets, dies and moulds. Aluminium alloy 7075 (AA7075) is an alloy, with zinc as the principal alloying element. It shows good ductility, high strength, toughness, and fatigue resistance. It is one of the most used aluminium alloys for highly stressed structural applications and is widely applied in aircraft structural parts.By considering the application of AA7075 and uses of the milling process in product manufacturing, the present work focuses on studying the effect of End milling process parameters in the milling of AA7075 plate by varying three distinct parameters: Cutting speed (S), Feed (f) and Depth of cut (d). The output parameters measured were Material Removal Rate (MRR) and Hardness (BHN) variation on the machined surfaces. The BHN of the machined surfaces varied from 178 to 260 BHN. Similarly, the MRR varied from 1500 to 13200 mm3/sec. The down milling experiments were conducted as per Taguchi’s L9 orthogonal array on a 6 mm thick plate using a solid carbide end mill cutter of 10 mm diameter.The effect of milling process parameters on selected responses was analyzed, and the optimization of process factors for maximization of MRR and hardness was carried out to improve the machinability of AA7075 alloy.

Operational behaviour of graded diamond grinding wheels for end mill cutter machining

The varying related material removal rate during deep grinding of cemented carbide end mill cutters results in an unevenly wear of the grinding wheel. This study therefore presents a simulation-based model for the load-adjusted design of grinding wheels to achieve balanced radial wear, as well as an evaluation of this model. The related material removal rate along the width of the grinding wheel is determined by a Dexel based material removal simulation for different end mill geometries. Based on these results an equation is derived to adapt the abrasive layer properties to the local load differences. Three grinding wheels with different types of gradients are then manufactured by a grinding tool manufacturer based on this equation. These and two grinding wheels with constant abrasive layer properties are used for deep grinding of ten end mills each. Afterwards the radial wear of each grinding wheel is measured by a confocal microscope. An analysis of the cutting edge chipping is done to evaluate the influence on the graded grinding wheels on the cutting edge quality. It was found that a reduction of the wear difference over the grinding wheel width of 52% and an improved cutting edge quality can be achieved by using graded grinding tools. This allows the time intervals between dressing steps to be increased without compromising the accuracy of the grinding process, thus also increasing its productivity. Finally, this article shows that the presented model allows for a more balanced wear behaviour, but has to be extended by considering further factors influencing radial wear.

Novel application of SiO2 nanofluid coolant for enhancing machinability over inconel 706 CNC end milling with conventional coolant

This comparative experimental study aims to improve machinability in terms of machining rate by novelly applying SiO2 nanofluid in the palace of conventional coolant for CNC end milling of Inconel 706. Two groups considered in this study are SiO2 nanofluid (CN) and Conventional Coolant (CC) based wet machining of Inconel 706 work material. The carbide end mill cutter of four flute, square end type used. Nanofluid with SiO2 concentration 4 wt% with less 5 nm sized particles considered. Sample size calculated 16 per group with G-power 80 % and alpha 0.05 settings. The key factors of cutting velocity, cutter feed rate, and depth of cut are varied by four levels. Material Removal Rate was calculated from the experimental observations and compared group wise in SPSS software. The test result shows a significance value of 0.015 (p less than 0.05), which reveals that observed results are significant. Novel application of SiO2 nanofluid in CNC end milling of Inconel 706 yielded 44.71 % higher material removal rate than conventional coolant.

Machinability study in milling of Ti-6Al-4V using cryogenic treated and coated tool

Ti-6Al-4V is one of the most important materials in the industry, 80% of which is utilised in the aerospace industry. Titanium alloys are difficult-to-machine because of their unique material properties. Machining hardened work materials with the correct process parameter levels in the manufacturing industry is a difficult task. Contour milling is the prime machining operation utilised in many industries to produce titanium parts. End mill cutters made of tungsten carbide are mainly utilized to machine hard and difficult-to-machine materials like titanium alloys. Current work is about the machining of Ti-6Al-4V using tungsten carbide end mill cutter following contour milling process for three different levels of input process parameters. Machining parameters have an effect on output responses like surface roughness, temperature and force. The input parameters has been broken down utilizing Box-Behnken design. A technique of multi-optimization GRA is used to identify the best machining parameter that enhances all output responses equally, like surface roughness, temperature, and force. Using this optimal value, comparative experiments were also conducted with coated and treated tools. As per the study's conclusions, cryogenic treated tool had a better surface finish, minimal force, and lower temperature.

A research on machining parameters during dry machining of Ti-6Al- 4V alloy

Aerospace structural components made of titanium alloy (Ti6Al4V) material requires end milling operations to achieve the required tolerance limits. Selection of optimal machining parameters to attain the desired surface quality and better tool life are the most critical task during finish machining of titanium alloys at dry machining conditions. Usually dry machining generates a very high cutting temperature and cutting force (feed force and tangential force) which affects the surface quality and tool life. In this research investigation, the effect of feed rate and depth of cut on cutting forces, temperature and surface roughness were analyzed during the machining of Ti6Al4V work-piece material. The experiments were carried out under dry machining conditions based on full factorial design with a milling tool named 3 fluted tungsten carbide end mill cutter coated with TiN. The selected feed rates for the experiments are 0.03, 0.06, 0.09 and 0.12 mm/rev and the depth of cut are 0.5, 0.75, 1 and 1.25 mm with a constant cutting speed of 40 m/min. By from the machining research it was found that feed of 0.06 mm/tooth and depth of cut of 0.75 can be chose for machining of titanium alloy. The cutting force was found by using peak and valley points acquired from the dynamometer for the postulated machining time. Moreover, it is observed that feed rate has the higher influence on cutting force and temperature when compared to depth of cut.

Influence of machining parameters on the polymer concrete milling process

The paper examines the wear of end mill cutters, the parameters of a workpiece’s surface layer and the values of cutting forces during the machining of polymer concrete, which is one of the most difficult-to-cut materials. Increased abrasive wear of the active cutting edges is a result of the heterogeneous structure of this material, and it has a negative effect on the cutting process, the durability of the cutting tools as well as the roughness of the workpiece. It is very important to determine the machining parameters for this material from a tool durability and quality of machining point of view. The research was divided into two stages. In the first stage, the appropriate machining parameters were determined based on the measurement of the components of the cutting force. In the second stage, durability tests of four end mill cutters were carried out. During the tests, the component cutting forces, tool wear and surface roughness were measured. The highest tool durability was recorded for the monolithic cemented carbide cutter with coating NC Mill G9F42120N 4F. Tools made of high-speed steel should not be used for machining polymer concrete, as they exhibited the highest intensity of tool wear. The rapid loss of machinability of these tools leads to a rapid increase in cutting force and the roughness of the machined surface. From an economic point of view, cemented carbide end mill cutters with coatings seem to be the appropriate choice for machining polymer concrete.

Optimization of process parameters in CNC milling of P20 steel by cryo-treated tungsten carbide tools using NSGA-II

ABSTRACT This article proposes an extensive experimental and microstructural analysis to study the consequences of deep cryogenic treatment (DCT) soaking duration on tungsten carbide end mill cutter on the machinability of P20 mold steel. A Box-Behnken design of response surface methodology (RSM) is utilized to collect data for the study. Cutting speed, feed rate, depth of cut and milling cutters subjected to various soaking durations are taken as important process variables which are a function of performance measures viz. tool wear rate (TWR), material removal rate (MRR) and surface roughness (R a). It is observed that cutting speed, feed, depth of cut and cryogenic treatment exhibit a considerable effect on performance measures. In the present study, NSGA-II multi-objective optimization technique is used to obtain the optimal process parameters of end milling process to enhance the productivity of the process. For this purpose, the developed RSM model is coupled with NSGA-II in MATLAB.

Influence of cutting conditions on surface characteristics in micro-milling of Ti-6Al-7Nb alloy

ABSTRACTTi-6Al-7Nb alloy is widely used in the manufacturing of medical implant. In this work, experimental study on micro-milling of Ti-6Al-7Nb is exemplified to analyze cutting conditions effect on surface texture. Process variables including cutting speed (vc), feed rate (fn) and depth of cut (ap) are considered. Responses in the form of surface topography variables including Average Surface Roughness (Ra), Maximum Average Profile Height (Rz) and Maximum Profile Peak Height (Rp) are measured. Dental implants are generally micro and miniature in nature to ensure functionality of a human bone. Hence, 20 micro-slot of 500 μm size are produced using Carbide end mill cutter under dry condition. Surface plots are drawn and are observed that ‘ap’ possess foremost effect on surface quality. Minimum ‘ap’ yields good surface finish of 0.1 µm. Analysis of variance also proves ‘ap’ effects on surface quality. Surface morphology study reveals grooves formation and particle deposition on finished surface at excessive ‘ap’ condition. Burr formation analysis shows the development of knife edge and wave-type burr for lower and higher ‘ap’ conditions, respectively. Hence, it is inferred that at lower ‘ap’ values (60 µm), desired surface finish of 0.1 µm is achieved in Ti-6Al-7Nb alloy that promotes better osseo-integration.

Quality characteristics optimization in CNC end milling of A36 K02600 using Taguchi’s approach coupled with artificial neural network and genetic algorithm

This study investigates surface roughness and energy consumption in a CNC end milling of plain low carbon steel (mild steel) A36 K02600 using a carbide end mill cutter. Taguchi’s L9 orthogonal array was adopted for designing the experimental runs considering several process parameters viz. cutting velocity, Feed rate, spindle speed and cutting depth in order to study their influence on the quality characteristics. Optimal control parameter combinations for minimizing surface roughness and energy consumption were evaluated from signal to noise ratio. Analysis of variance revealed the contribution of control factors on the quality characteristics. Numerical predictive models using linear regression and artificial neural network were developed to envisage the responses accurately. Multi-objective Genetic Algorithm optimization was exploited in order to obtain a specific set of control parameter which would optimize both the responses simultaneously. This study concludes that spindle speed (68.24% contribution) and feed rate (92% contribution) are the most responsible variables for surface quality and energy consumption respectively. The outcome of artificial neural network model and genetic algorithm confirm that both quality characteristics can be optimized simultaneously and Taguchi’s robust design approach is a successful tactic for optimizing machining parameters to achieve desired surface quality at low energy consumption. Improvement in surface quality and reduction in energy consumption were found to be 27.79% and 30% respectively. Low carbon steel is extensively accepted by the industries for its wide variety of which make this study physically viable.

Investigation on Cutting Forces and Surface Finish in Mechanical Micro Milling of Zr-Based Bulk Metallic Glass

Precision micro-component fabrication demands suitable manufacturing processes that ensure making of parts with good form and finish. Mechanical micro milling represents a flexible and powerful process that exhibits enhanced capability to create micro features. Bulk metallic glass (BMG) represents a young class of amorphous alloy material with superior mechanical and physical properties and finds appreciable micro scale applications like biomedical devices and implants, micro parts for sport items and various other micro- components. In the present work, an attempt has been made to analyze the influence of the cutting parameters like spindle speed, feed per tooth and axial depth of cut on the machinability of BMG, in mechanical micro-milling process. The micro-milling process performances have been evaluated concerning to cutting forces and surface roughness generated, by making full slots on the workpiece with solid carbide end mill cutters. The paper presents micro-machining results for bulk metallic glass machined with commercial micro-milling tool at low cutting velocity regime. Response surface methodology (RSM) has been employed for process modeling and subsequent analysis to study the influence of the combination of cutting parameters on responses within the selected domain of cutting parameters. It has been found that the effect of axial depth of cut on the cutting force components is remarkably significant. Cutting force components increases with the increase in axial depth of cut and decreases with increase in spindle speed. At low feed rate, cutting force in the feed direction (Fx, i.e., cutting force along x-direction) increases with a decrease in feed rate. This increase of force could be due to the possible ploughing effect. A similar pattern of variation has been observed with cutting force component in cross-feed direction (Fy) also. It has been found that effect of feed per tooth on the roughness parameter Ra is remarkably significant. Surface roughness increases with feed per tooth. Axial depth of cut does not contribute much to the surface roughness. Surface roughness decrease with the increase of spindle speed.

A hybrid approach to multi response optimization of micro milling process parameters using Taguchi method based graph theory and matrix approach (GTMA) and utility concept

Nowadays, it is required to produce micro products with high dimensional accuracy to use them in different applications like aerospace, electronic and optics. The objective of this study is to investigate influence of process parameters on surface roughness (Ra and Rq), tool wear and cutter vibration in micro milling of AISI304 stainless steel. According to orthogonal array of L27, twenty-seven experiments were conducted on the workpiece with carbide end mill cutter at different levels of spindle speeds, feeds and depth of cuts. A hybrid approach of Taguchi method based graph theory and matrix approach (GTMA) and utility concept was used for multi response optimization of process parameters. The GTMA was used to calculate weightage of four responses as per user’s opinion or preference. The utility concept was used to calculate utility value of four responses using preference scale. Mean utility values of responses are analyzed with Taguchi method and analysis of variance. The optimum process parameters for the minimization responses were found to be 6000 rpm of spindle speed, 95 µm/teeth of feed and 50 µm of depth of cut. The predicted responses at optimal process parameters are Ra = 0.534 µm, VB = 70.861 µm, Amp = 54.395 µm and Rq = 0.894 µm. A confirmation test was also carried out to verify the results.

Effect of cryogenic treatment of tungsten carbide tools on cutting force and power consumption in CNC milling process

In this paper, the effect of Deep Cryogenic Treatment (DCT) soaking duration on tungsten carbide end mill cutters on cutting forces and power consumption during machining P20 mold steel in CNC milling machine is investigated and optimized the process parameters. The data collected for the study are based on Box–Behnken design of response surface methodology. Cutting forces and power consumption are considered as important performance measures which are functions of decision variables viz. cutting speed, feed, depth of cut, and end milling cutting tools subjected to different soaking duration. The percentage contribution is calculated based on ANOVA to identify most influencing parameter on cutting forces and power consumption. The study revealed that cryogenic soaking duration exhibits most significant effect on cutting forces and power consumption followed by cutting speed, feed, and depth of cut. Regression analysis is carried out to relate the process variables and performance measures. Finally, a non-dominated sorting Algorithm (NSGA-II) is proposed to optimize the process variable to obtain the desired optimal solutions. The results indicate DCT tool soaked for longer duration is minimizing the cutting forces and power consumption when compared to untreated tool.

The Effect of Process Parameters on Material Removal Rate and Dimensional Variation of Channel Width in Micro-milling of Aluminium Alloy 6063 T6

Micro milling is the process of manufacturing 3D complex structures with high accuracy, low cost and good surface finish. It has a wider scope in variety of applications such as micro fluidics for transportation of biological materials, micro heat exchangers for micro electromechanical systems (MEMS), etc.In this paper micro milling process is used under dry condition to produce micro-channels on Aluminium alloy 6063 T6 using Tungsten Carbide end mill cutter of 400 µm diameter. The effect of process parameters such as spindle speed, feed rate and depth of cut on material removal rate (MRR) and dimensional variation of channel width (Wvar) is investigated. Design of experiment is done by Taguchi L16 orthogonal array. ANOVA is carried out to analyze the experimental results. The optimum conditions obtained from Taguchi method for optimizing MRR during micro milling of Aluminium alloy 6063 T6 are feed rate of 4.5 mm/min, depth of cut of 0.064 mm and spindle speed of 2500 rpm. Depth of cut is the most significant factor of about 63.10 % followed by feed rate of 33.30 % and the spindle speed is least significant factor about 1.16 % influencing MRR. Similarly the optimum conditions obtained from Taguchi method for optimizing Wvar are spindle speed of 2000 rpm, depth of cut of 0.048 mm and feed rate of 1.8 mm/min. Spindle speed is the majorly contributing of about 53.05 % in obtaining optimal Wvar,depth of cut of 26.13 % and feed rate has very less contribution of 3.51 %.

Tool Wear of Aluminum/Chromium/Tungsten/Silicon-Based-Coated End Mill Cutters in Milling Hardened Steel

In turning hardened steel, polycrystalline cubic boron nitride (cBN) compacts are widely used, due to their high hardness and high thermal conductivity. However, in milling hardened steel, fracture of cBN cutting tools readily occurs because they have poor fracture toughness. Therefore, coated cemented carbide tools, which have good fracture toughness and wear resistance, are generally and widely used. In this study, hardened steel (ASTM D2, JIS SKD11, 60HRC) was milled with three physical vapor deposition coated cemented carbide end mill cutters in order to determine effective tool materials for milling hardened steel. The coating films used were two types of aluminum/chromium/tungsten/silicon-based-coating films and (Ti,Al)N-coating film. The two types of aluminum/chromium/tungsten/silicon-based-coating films are a new type of coating film, and the Type I and Type II coating film was a two-layered and multi-layered structure, respectively. The following results were obtained: (1) In milling hardened steel at a cutting speed of 2.5 m/s, Type II coating film was the best coating material among the three types of coated film. Type I coating film was superior to (Ti,Al)N-coating film. (2) The critical scratch load of both Type I and Type II of over 130 N became larger than that of the (Ti,Al)N-coating film of 65 N. (3) The multi-layered structure is expected to improve the tool life.

Experimental investigation and analysis of factors influencing delamination and surface roughness of hybrid GFRP laminates using Taguchi technique

Purpose The paper aims to develop a mathematical model for delamination and surface roughness during end milling by using response surface methodology (RSM) and to determine how the input parameters (cutting speed, depth of cut, helix angle and feed rate) influence the output response (delamination and surface roughness) in machining of hybrid glass fibre reinforced plastic (GFRP; Abaca and Glass) composite using solid carbide end mill cutter. Design/methodology/approach Four-factor, three-level Taguchi orthogonal array design in RSM is used to carry out the experimental investigation. The “Design Expert 8.0” is used to analyse the data collected graphically. Analysis of variance is carried out to validate the model and for determining the most significant parameter. Findings The feed rate is the cutting parameter which has greater influence on delamination (88.39 per cent), and cutting speed is the cutting parameter which has greater influence on surface roughness (53.42 per cent) for hybrid GFRP composite materials. Both surface roughness and delamination increase as feed rate increases, which means that the composite damage is larger for higher feed rates. Originality/value Effect of milling of hybrid GFRP composite on delamination and surface roughness with various helix angles of solid carbide end mill has not been analysed yet using RSM.

Experimental Investigation and Finite Element Analysis of Milling of Ti-6Al-4V Titanium Alloy by Studying Cutting Forces and Chip Microstructure

Titanium alloys are commonly used for many aerospace and medical applications because of their properties like high strength to weight ratio, corrosion resistance and heat treatment capabilities. But, due to the factors like low thermal conductivity and chemical reactivity with the cutting tool, it poses a challenge for the machining operations. In this study, a 3D Finite Element Model of the milling process of Ti-6Al-4V, titanium alloy has been developed using Deform 3D FE software. Milling was done experimentally under different speeds and feed rates using a Tungsten carbide end mill cutter. The cutting forces obtained from FEM study were compared and validated with the experimental results. The machinability of the Titanium alloy was investigated using cutting forces and chip microstructure.