Flank Surface Research Articles

Performance assessment of graphene oxide based nano-cutting fluids during sustainable hard turning through synthesis, characterization and machinability investigation

Achieving sustainability in manufacturing necessitates the implementation of eco-friendly solutions by adopting environmentally friendly coolants with cost-effective, energy-efficient and cleaner production processes without posing any risk to the operator's health. In this current work, mineral oil-based graphene oxide (GO) nano-cutting fluids of different concentration (0.05, 0.1, 0.2, 0.3, 0.4, 0.5 % wt.) are synthesized and their characteristics such as rheological, thermo-physical and tribological properties along with their stability and toxicology impact are thoroughly investigated. Further, the influence of nano-cutting fluid concentration on machinability and sustainability aspects during hard turning such as flank wear, surface integrity, power consumption, cutting temperature, carbon and noise emissions are investigated. According to the result an enhancement of 28.83 % and 29.54 % in viscosity and thermal conductivity have been recorded when concentration of nanofluid increases from 0.05 % to 0.5 %. GO nano-cutting fluids shows anti wear and friction reduction properties by providing excellent lubricious properties, as a result coefficient of friction has been reduced up to 28.36 % at 0.5 % wt. GO compared to plane mineral oil. A notable reduction in flank wear, cutting temperature, surface roughness, cutting temperature, power consumption, carbon emission and noise emission were noticed to be 25.96 %, 27.82 %, 23.86 %, 25.22 %, 11.66 % and 2.72 % respectively when the concentration of GO nanoparticles increases from 0.05 % to 0.5 % wt. Smoother surface with minimal defect has been noticed from the SEM and AFM image of machined workpiece at highest concentration (0.5 % wt.) of GO due to the synergetic effect of GO nano-cutting fluid and dual nozzle MQL system.

Sustainable hard machining under zirconia nano-cutting fluid: A step towards a green and cleaner manufacturing process

The present study deals with the machinability (flank wear, surface integrity, cutting temperature and power consumption) and sustainability (Carbon emission and noise emission) investigations during hard machining under dual nozzle assisted novel ZrO2 based nano fluid MQL condition considering Taguchi L27 OA design of experiment. 0.3 % wt. ZrO2 nanofluid MQL medium effectively reduce cutting temperature and found as 65 °C, which shows the effective cooling and lubrication properties of zirconia nanofluid. Improvement in surface quality has been observed with lower rate of flank wear. Depth of cut and feed are found to be the most influential factor affecting power consumption and carbon emission with contribution of 47.213 % and 60.861 % respectively. Noise emission mostly affected by the depth of cut with a contribution of 43.40 %. Optimal parametric condition yields d: 0.1 mm, f: 0.1 mm/rev and v: 80 m/min through WASPAS and sustainable towards manufacturing industries for cleaner hard machining.

Research on gear flank surface defect detection of automotive transmissions based on improved YOLOv8

Abstract In industrial production, the manufacturing processes may introduce defects on the gear flanks of transmission gears, potentially leading to premature failures and diminished performance. The early detection and precise assessment of surface defects on transmission gear flanks are critical for maintaining the safety, reliability, and cost-effectiveness of automobiles. At present, the principal approach for identifying defects on automotive transmission gear flanks predominantly involves manual visual inspections, supplemented by fluorescent magnetic particle testing. However, this approach suffers from low accuracy and efficiency. Consequently, this paper presents a defect detection algorithm that leverages an enhanced YOLOv8 model to facilitate the efficient detection of surface defects on automotive transmission gear flanks. Initially, the collected image data underwent data augmentation and exploratory analysis, which informed targeted enhancements. Subsequently, the YOLOv8 algorithm was thoroughly examined. The SPPE architecture was incorporated into the backbone network, and the DCNv4 module was integrated to boost the model's capability in detecting irregular defects. In the neck network, the BiFormer attention mechanism was implemented to enhance detection performance for small-scale defects. Moreover, the newly developed MASFF_Head structure was adopted as the detection head to augment detection efficacy for multi-scale defects. Additionally, the bounding box-loss function was substituted with the WIoU loss to improve performance on low-quality samples. Experimental results demonstrated that the mAP@0.5 of the refined YOLOv8 network model reached 86.1%, marking a 2.8% increase over the original model and significantly boosting detection accuracy. When compared to other deep learning models, the enhanced YOLOv8 model exhibits considerable superiority in terms of detection precision and efficiency. The P value and R value achieved were 82.9% and 80.8%, respectively, with a detection time of 21.6 milliseconds. This underscores the method's effectiveness and reliability in detecting automotive transmission gear defects, underscoring its pivotal role in facilitating automated detection processes on industrial production lines.

High-Speed Milling of Hardened AMS 6260 Alloy Using Radius End Mill (Effect of Cutting Conditions on Flank Wear and Surface Roughness)

AMS 6260 alloy is a nickel-chromium-molybdenum steel containing Ni, Cr, Mo, with Fe as the main component, and is one of AMS (aerospace materials specifications) in the United States. This material has high hardenability and high toughness. For this reason, it is used as a material for parts that require high toughness, such as gears in aircraft engines. However, while AMS 6260 alloy after heat-treatment has high hardness, it significantly reduced machinability. Therefore, it is extremely difficult to achieve high efficiency and high accuracy in the cutting process of AMS 6260 after heat-treatment. In this paper, the experimental milling of the hardened AMS 6260 alloy after heat-treatment is conducted under some cutting conditions using a coated cemented carbide radius end mill, and the effect of cutting conditions on the flank wear and surface roughness is investigated. As a result, optimal cutting conditions on the tool wear and surface roughness were clarified.

Sustainable machining with LN2 in turning of super duplex steel

ABSTRACT Currently, the majority of industries rely on turning processes to manufacture mechanical products. The selection of coolant is of paramount importance in the pursuit of sustainable manufacturing. Super duplex steel’s machinability during the turning process is the subject of the present investigation. The machining characteristics, such as Flank wear (Fw) and Surface roughness (Ra), were analyzed by varying the control parameters, including cutting velocity (Vs), feed rate (f), and cutting conditions i.e. Dry, Nanofluid + MQL (NMQL), LN2 + MQL (LMQL), through a constant depth of cut (d) using a Taguchi L27 orthogonal array. The results demonstrated that the LMQL approach is more efficient as it reduces the Ra by 77%, 54%, and Fw by 83%, and 93%, respectively, in comparison to the dry and NMQL conditions. Additional research on microstructure revealed that the character of the grains is improved when the surface is machined with LMQL in comparison to other cutting conditions.

Experimental investigation on turning Inconel 713C under different cooling conditions using a new honeycomb-textured tool

ABSTRACT Tool surface texturing is a new sustainable method for machining hard-to-machine materials. The present study focuses on the new honeycomb texture (mimic of bee’s honeycombs) containing hexagons forming between thin vertical walls. The important novelty in this work is the cutting performance of honeycomb texture on Inconel 713C was examined under cutting parameters and different cooling conditions: dry untextured (T1), dry textured (T2) tool, impregnated solid lubricant (hexagonal boron nitride (hBN)) textured tool (T3), MQL (coconut oil) with textured tool (T4), and NMQL (0.20 wt.% hBN + coconut oil) with textured tool (T5). Compared to plain tools, NMQL to honeycomb texture reduced flank wear by 53.2%, roughness by 43.2%, turning force by 27%, and cutting temperature by 47.7%. Honeycomb texture with MQL (T4) and NMQL (T5) reduces flank surface Ni element diffusion during turning. Nanofluid-textured inserts (T5) demonstrated higher shear angles, lower chip curl diameter, and shorter tool-chip contact length than other conditions.

OPTIMIZATION OF MACHINING AA4015/B4C METAL MATRIX COMPOSITES BY TAGUCHI METHOD

This research investigates the impact of dry machining AA4015/B4C MMCs (metal matrix composites) utilizing an uncoated B4C insert on Flank wear (VBc) and surface roughness (Ra). This work attempts to close the knowledge gap on the effects of cutting parameters (feed, depth of cut, and speed) on tool wear and surface quality in machining technology. The primary rationale lies in optimizing machining processes for MMCs, known for their challenging machinability due to their tough metallic matrix and hard ceramic reinforcement. The study’s significance is underscored by the exploration of optimal processing parameters to minimize Flank wear and improve surface roughness, crucial factors influencing component quality and lifespan. Specifically, the research identifies v1-f1-d3 (VBc) and v3-f1-d3 (Ra) as the best process parameter combinations, significantly reducing both VBc and Ra. The obtained mathematical models for VBc and Ra provide statistically significant insights into the relationships between cutting variables and performance characteristics. The employment of Taguchi’s L9 orthogonal array proves invaluable in achieving these optimized process parameters efficiently. The Taguchi method’s advantage lies in its ability to systematically explore numerous variables and their interactions with minimal experiments. By reducing the number of trials required, this methodology streamlines the optimization process, saving time, resources, and costs while delivering enhanced machining performance for MMCs. This research, through its systematic approach and emphasis on optimized parameters, contributes to the advancement of machining techniques for MMCs, holding implications for various industrial applications demanding high-performance materials.

Study on force-thermal characteristics of ball end milling cutter with chamfered edge and micro-textured flank face

Micro-texturing can significantly improve the cutting performance of tools. During the titanium alloy cutting process, the cutting depth is relatively small, and the flank face mainly bears the friction. To overcome this issue, this study attempts to explore the influence of the micro-texture of the flank surface and chamfered edge on the cutting performance of the ball end mill. It is proved that the micro-texture of the flank surface of ball end milling cutter can reduce the actual contact area and friction, and thus reduce the cutting force. The increase of chamfering width and Angle changes the chip state and provides a good heat dissipation environment. Under the combined action of chamfered cutting edge and micro-texture, the force and heat in the milling process are reduced, and the tool life is increased to some extent. The results show that the optimum combination of chamfering and micro-texture parameters is as follows: chamfer angle is 10°, chamfer width is 100 µm, diameter of the micro-circular pit is 70 µm, pit spacing is 125 µm, and distance from cutting edge is 110 µm.

Experimental Investigation on Surface Characteristics of Finish Hobbed Gear using Grey Relational Analysis

Introduction: Spur gears are important for transferring motion and power among shafts. The surface characteristics of these gears are important for their life and smooth operation. To improve profitability and customer satisfaction, a study was conducted to analyze the surface quality of spur gears produced through CNC hobbing machining. Objectives: The objective this investigation is to conduct experimental trials to estimate the best hobbing parameters to minimize surface roughness and microgeometric deviations. In this investigation, effect of varying cutting speed and feed rate on surface finish have been reported. Methods: An experiment are conducted according to Taguchi L9 experimental design. Grey Relational Analysis is performed to estimate the optimum machining parameters. Results: The experimental finding reveals, at cutting speed 400 rpm, the feed rate 8 mm/min, and depth of cut 3.91 mm gives good quality of surface (Ra 0.5530). The gear hobbing process has increased to a greater level of performance. The roughness of the flank surface and microgeometry deviations decreases with an increase in hob cutter speed. Conclusions: This ultimately reduces the inherent vibrations between the hob cutter and the gear blank, thus minimizing microgeometric deviations. The variation in feed rate was noticed and had a very significant impact on the efficiency and surface quality of the gear. The study recommends that a cutting speed of 400 rpm is the most effective for obtaining the best results.

Optimisation of machining parameters of AISI 304L stainless steel with the least error method using Taguchi, RSM, and ANN

ABSTRACT This study has been conducted on the machining of AISI 304 L stainless steels, which are difficult to machine, have chip-breaking problems, and therefore cause premature wear. A full factorial experiment was designed, and the experiments were conducted at five different inserts, five different cutting speeds, two different feeds, and three different cutting depths. As a result of the experiments carried out, the flank wear and surface roughness values were measured. Utilising Taguchi, Response Surface Methodology (RSM), and Artificial Neural Networks (ANN), interpolation estimates were obtained for flank wear and surface roughness, followed by optimisation investigations. The method with the least error was selected by examining the estimation results. Different methods confirm each other, and simultaneously, the chosen method strengthens the estimation. Confirmation experiments were performed for the parameters giving the optimum value. The optimal outcomes in the range of cutting tips and parameters were obtained with the insert with Al2O3+TiCN coating at a cutting speed of 170 m/min, a feed of 0.13 mm/rev, and a depth of cut of 1.1 mm. It has been seen that the validation experiments agree with the actual and estimated values.

Tool life experiment of coated cermet during nodular cast iron turning

AbstractIn this study, the application of physical vapor deposition (PVD) coatings on various cermet substrates for the machining of nodular cast iron was investigated, given that cermet materials are traditionally not the primary choice for such applications. Through the evaluation of key parameters including wear on the flank face and surface roughness, and with vibration analysis serving as a supplementary measurement, it was discovered that machining stability is compromised by the inherent brittleness of cermet and the adhesion of material on the rake face. While the application of coatings was found to extend tool life, the cermet-coating combinations did not surpass the performance of other materials such as cemented carbide with multi-layer coatings. Notably, the stability of surface roughness across various stages of tool wear was observed.

Comparing Bio-Ester and Mineral-Oil Emulsions on Tool Wear and Surface Integrity in Finish Turning a Ni-Based Superalloy

The paper compares the performance of two bio-ester and two mineral-oil emulsion metalworking fluids (MWFs) in finish turning an Inconel 718 alloy bar with a high hardness (HB 397 – 418). In this study, a coolant with a lean concentrate diluted at 6.5% to create an emulsion with stabilised water hardness was used to prepare each MWF. The finish-turning method used a small tool nose radius (0.4 mm) and small depth of cut (0.25 mm) to turn down 52.2 mm diameter bars in multiple passes to reach a maximum tool flank wear of 200 µm. In each MWF turning test, the tool flank wear, cutting forces, and surface roughness were measured against cut time. Chips from each MWF turning test were also collected at the same cut time instances. The surface and subsurface integrity on a workpiece obtained from each MWF turning test were compared by using a new unworn tool. Overall, for the machining parameters studied, the findings suggest the bio-esters were capable of equivalent machining performance as the mineral-oil emulsions, apart from one bio-ester that displayed improved surface roughness. Common to all MWF turning tests was a change in the chip form at low flank wear, which is discussed. Further findings discussed include the sensitivity of the concentration of the MWF diluted in the emulsion and the effect of the workpiece hardness within the batch used, with useful recommendations to improve the finish-turning method for the assessment of MWFs.

Hybrid deposition of AlTiN/WN multilayer films with low compressive stress at low temperature

AlTiN/WN multilayer films with low compressive stress were deposited by arc evaporation and DC magnetron sputtering at a low temperature. The phase structure, morphologies, mechanical properties, wear behavior, and cutting performance of the AlTiN/WN multilayer films were evaluated. The results show that all the as-prepared AlTiN/WN multilayer films have fcc structure and exhibit (111) preferred orientation. The lowest value of −1.7 ± 0.3 GPa for compressive stress was obtained under low-temperature deposition. The film hardness increases as the temperature increases. High-temperature deposition provides higher energy to grow a dense film, which improves the film hardness. Increasing the WN layer thickness reduces the adhesion strength of the film. Compared with room temperature, the friction coefficients of the films against stainless steel reduce at high temperatures. This was attributed to lubricative oxides WOx formed on the wear surface at high temperatures. Dry cutting experiments were conducted and the longest service life of the coated tool reaches ∼3730 m. The worn flank surface shows that both adhesion and abrasive wear dominate the failure of the coated tools.

Profile Optimisation of a Solid Modular Hob in the Machining of Gears Made of Classic and Unusual, Innovative Materials.

Modular hobs are tools with very complex geometry. Regardless of the material of the gear wheels, they determine the accuracy of the gears made in the hobbing machining process. Gears are made of various, often innovative materials depending on the requirements. Sometimes, the materials are characterised by very high hardness (over 65 HRC). The mathematical basis for describing the faces of a hob presented in the article allows for modifying the rack profile shaping the gear wheel's teeth. The model's universality makes it possible to perform numerical simulations of the influence of individual parameters of the hob creation process (geometry of the grinding wheels and their setting in the shaping process) on the profile of the rake and flank surfaces. The cutting edge (rack edge) is the locus of points belonging to both of these surfaces and thus directly impacts the accuracy of the gear wheel that is shaped in the hobbing process. The article summarises the authors' long-term cooperation with the industry, resulting in a series of articles devoted to hobs. The issues presented in the article are significant to the machinery industry and hob manufacturers.

Parametric optimization of the machining performance of Al-SiCp composite using combination of response surface methodology and desirability function

In this study, machining parameters such as speed, feed, and depth of cut were optimized for maximum material removal rate (MMR) of Al-SiCp composite turned with a tungsten carbide tool using response surface methodology based central composite design while keeping tool wear and surface roughness within specified limits. The influence of turning factors on flank wear and surface roughness height was investigated using regression models. ANOVA analysis is used to assess the appropriateness of the projected models and the significant factors for response optimization using the desirability method. The percentage contribution of the significant machining parameters and their interactions for optimization of the response is determined using ANOVA technique. Cutting speed is found to be the most significant factor for flank wear, average roughness height Ra and maximum roughness height Rt with contribution of 65.38%, 58.7% and 37.9% respectively for optimization of the response. Confirmation tests were carried out and the percentage error between observed and predicted value of the responses is found to be within acceptable limits, demonstrating that the created models correlates well with the experimental data. Under optimal conditions, utilizing a tungsten carbide tool can prove to be a cost-effective alternative for turning Al-SiCp composite.

Drilling performance of micro-textured twist drill bit for TI-6AL-4V alloy: Validated FEM and statistical approaches

The titanium alloy, particularly Ti-6Al-4V, is an extensively demanded material in diverse sectors because of its superior physical and chemical properties. Nevertheless, the inherent hardness of the material causes challenges during machining operations. The alloy's heat-resistance characteristic induces increased friction and heat generation on cutting tools, ultimately causing a decrease in the tool life. In an attempt to overcome this issue, numerous forms of surface texturing have been investigated with the aim of improving the tribological characteristics of the material. The aim of the present investigation was to enhance the cutting performance of drill bits by implementing micro-textured patterns, hence minimizing thrust force, torque, and tool temperature. The combined effect of three distinct micro-textured geometries on a drill bit's flank, flute, and margin surfaces, with the influence of coating conditions, on the performance of drilling operations was investigated. The Finite Element Method (FEM) was used to perform a range of varied drilling operations. The Grey Relation Analysis (GRA) and General Linear Model (GLM) were employed to assess and compare the drilling performances with respect to thrust force, torque, and drill bit temperature. It was found that the square-sectioned textures on the side face exhibited the most obvious influence on the drilling performance. In the meantime, the textures found on the flute face were identified as having a comparatively smaller influence. The ideal configuration for the drill bit entailed a flank face with a square sectioned texture, a flute face without any texture, a margin face with a square sectioned texture, and a hard coating. As a result, the current situation substantially reduced cutting forces, tool wear, and tool temperature by 51 %, 20.5 %, and 23.4 % compared to the drilling condition without textured drill bits.

Effects of shear thickening fluid preparation on tool performance in the milling of Ti6Al4V titanium alloy

The performance and quality of tools can directly affect the efficiency and quality of machining, and preparation methods of the cutting edge have an important impact on the machining performance and tool life. As a method that can adapt to the unique and complex geometry of the cutting edge, shear thickening passivation is an innovative application of shear thickening fluid. In this study, the effects of shear thickening passivation methods on the milling performance and tool life of cemented carbide milling cutters were investigated. The cutting force, tool wear, tool life and surface morphology were analyzed by side milling Ti6Al4V titanium alloy with cemented carbide milling cutters that were unprepared, drag finished and shear thickening passivated, respectively. The results demonstrate that shear thickening passivation can remove the micro-defects of the tool after grinding. After shear thickening passivation, the cutting edge is rounded, and the rake and flank surfaces are flat, and the defects of the cutting edge are removed. Compared with the unprepared tool, the life of the shear thickening passivated tool is improved by 50 %. Therefore, the shear thickening passivation can effectively improve the tool life and tool performance and significantly reduce the economic cost in practical machining.

Effect of TIBW anti-wear coating on cutting tools for milling of nickel alloys on tool wear and integrity of state of the technological surface layer

In the article, research was carried out to determine the impact of the TiBW anti-wear coating on the operational properties of cutting tools for machining nickel alloys. The dynamics of tool wear were determined based on changes in the components of the total cutting force, microscopic observation of wear on the flank surface, and observation of wear based on SEM images. The condition of the technological surface layer was also determined in the form of changes in the microstructure morphology and hardening of the surface layer. The research was compared to a reference tool with the same geometry with an AlTiN coating. It was shown, among other things, that TiBW coatings can be used successfully for cutting tools for machining nickel alloys, and that the wear dynamic is similar to those of tools with the AlTiN coating. The analyses confirmed the significant thermomechanical impact of the cutter during machining, manifested by chipping and a tendency to strengthen the processed material. Based on observations of the microstructure of the surface layer after processing, it was shown that the thermal conductivity of the TiBW coating may be lower than that of the AlTiN coating, which is reflected in the different depths of the thermomechanical interaction zones.

Investigation of machinability characteristics of Inconel 713C using new novel honeycomb and broken-parallel texture cutting inserts with graphene-based solid lubricants

The present investigation aims to investigate the machinability performances of graphene solid lubricant (S) deposited on dimple texture (T1-S), novel honeycomb texture (T2-S), and novel broken-parallel textures (T3-S) during dry turning of Inconel 713C has been carried out and compared with dry (D) textured tools (T1-D, T2-D, and T2-D). L24 orthogonal design was used to design the experiments by considering conditions (dry and solid lubricant), textured type, cutting speed, and feed rate. The experimental results reveal that the honeycomb without and with graphene (T2-D and T2-S) effectively reduced the generated cutting temperature by 14.5 % and 22.4 %, cutting force by 34.6 % and 39.4 %, surface roughness by 14.3 % and 22.4 % and tool flank wear by 11.9 % and 2.3 % compared dimple and broken parallel textured inserts. The honeycomb tool (T2-D and T2-S) exhibited shear angle increased by 7.45 % and 6.5 % and 29.3 %, and 33.33 % than dimple under dry and graphene textured cutting tool. The chip reduction coefficient was <1.5, resulting in an increased shear angle and decreased friction coefficient in graphene-deposited honeycomb texture conditions. The major mechanism credited to the improved performance of honeycomb with graphene tool was reduced chip curl diameter and chip width by 3.3 % and 5.7 % compared to other tools. SEM images showed that all textured inserts' primary tool wear mechanisms on the tool surface were built-up edges, micro-chipping, adhesions, and abrasions. EDS analysis and following elemental plotting showed the strong presence of workpiece constituents on the flank surface. But, the influence of adhesion and abrasion was more noticeable for all dry-textured tools. The findings of this study indicate that honeycomb textured tools are a superior alternative to dry machining of Inconel 713C. Additionally, broken-parallel textured tools were more effective than textured dimple tools.

Influence of self-lubricating elements (SrSO4, Mo, and CaF2) on machining performance of Al2O3-ZrO2 (Y2O3)-NiCr-Ag cutting tool over a wide cutting speed range

The Zirconia toughened alumina (ZTA) is the commonly used cutting tool material as it has superior mechanical properties. However, the poor tribological properties made it not suitable for dry machining. Various researchers added many additives to ZTA base tool to machine different workpiece materials for use in various applications. Still, it experiences many difficulties at various cutting speeds during machining. To overcome this, a novel composite tool was fabricated in the present study by adding the following self-lubricating elements such as, NiCr, Ag, Mo, SrSO4, and CaF2. The cutting performance was investigated by comparing the self-lubricating cutting tools (SLTs) with the base tool regarding cutting force, coefficient of friction, and surface roughness. The results showed that the addition of SrSO4 and Mo at 10 wt.% and CaF2 at 5 wt.% obtained superior mechanical and tribological characteristics. The generation of the following phase, viz., MoO3, Mo4O11, and Ag2MoO4, CaMoO4, and CaSO4, are responsible for the better performance. The additives restrained the transformation of t-ZrO2 to m-ZrO2 resulting in improved hardness and wear characteristics leading to strong protection of the self-lubricating layer formed on the tool flank surface, causes for performance improvement. The wear of the SLTs is primarily dominated by abrasion and adhesion, whereas the base tool is dominated by abrasion, adhesion, chipping, and cracking.