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This work investigates the characterization of a cryo-processed AlTiN-coated tool and its turning characteristics for Inconel 600. The microhardness was enhanced by 3.68% under cryo-treatment when compared with the as-received condition of the inserts because of the wear-protective coating formed on the surfaces of the cutting tool. This was confirmed through EDS elemental analysis of carbon element growth and change in chemical composition, as well as XRD phase analysis. Next, this work studied the influence of cryo-treated inserts on roughness and mechanism of wear during turning Inconel 600 using varying cutting velocities (37, 60, and 100 m/min) under dry conditions. The output responses revealed that the use of cryo-treated tools reduced the roughness of the product by 11–27% and the rate of tool wear when compared with the untreated conditions. Due to these enhanced properties with cryo-treated conditions, it remains a suitable cutting tool for a significant contribution to sustainable machining toward dry cutting of aerospace alloys. [ABSTRACT FROM AUTHOR]

This study describes the cutting performance of Monel 400 alloy using a cryo-treated AlTiN carbide tool. The AlTiN carbide tool was cryo-treated at −196°C for 24 h of soaking at a cooling rate of 0.5°C/min and then tempered at 200°C for 2 h at a heating rate of 0.5°C/min. In this work, we evaluate and compare the hardness, composition, and phases of untreated and cryo-treated AlTiN-coated carbide inserts and also the turning performance of Monel 400 alloy. The machinability characteristics of cutting temperature, turning force, roughness parameter (Ra), form of chip, and SEM-EDS analysis of turned inserts are evaluated and then compared. It was found that the cryo-treated (CT) inserts offered a higher hardness value by 1.5% than the untreated (UT) ones, due to the formation of a new hard surface coating with cryogenic treatment. Cryo-treated AlTiN coated carbide inserts provided the following benefits over untreated ones: lower the cutting temperature at the cutting zone by a maximum of 10%; decreased the cutting force by 6–14%; reduced the Ra values in the turned surface by a maximum of 83%; a reduction in the size of the serrated form of chip; a reduced rate of insert wear; and lower deposition of work material constituents in the turned insert. The reason is enhanced resistance to wear due to an increase in hardness and the formation of a new hard surface coating with cryo-treated AlTiN coated carbide inserts, which was confirmed by analyses of hardness, SEM coupled with EDS, and X-ray diffraction. From the comparison of the characterisation and machinability indices of untreated and cryo-treated AlTiN coated carbide inserts, it was found that the cryo-treated AlTiN-coated carbide inserts provided the favourable turning performance of Monel 400 alloy. [ABSTRACT FROM AUTHOR]

This work investigates the performance of modified tungsten carbide inserts when turning supermartensitic stainless steel with cutting fluid and/or air jet applied in two directions: either cutting fluid under high pressure or compressed air under low pressure supplied on the back of the chip (through a hole produced near the principal cutting edge), together with either cutting fluid or compressed air, both under low pressure, directed at the clearance face. Tool performance is evaluated by means of the principal cutting force, temperature distribution (using FEM), visual evaluation of the rake face, morphology of the chips and the quality of the machined surface. The findings indicate that the groove reduces the cutting force when dry cutting. Cutting fluid applied under low pressure at the clearance face is more efficient in decreasing both the cutting force and chip temperature than cutting fluid at high pressure supplied at the back of the chip. A chrome oxide layer is formed on the chip when air jet is applied, thus leading to an unfavorable cutting condition. The simultaneous application of cutting fluid under high pressure to reach the back of the chip and compressed air supplied through the clearance face provides the best surface quality. [ABSTRACT FROM AUTHOR]

Purpose: Despite the accuracy of heart rate (HR) as an indicator of the aerobic engagement has been evaluated in several intermittent on-court activities, its validity as an oxygen uptake (${\dot V_{{O_2}}}$ V ˙ O 2 ) indicator during shuttle running over short paths remains uncertain. Moreover, it is unclear whether speed may affect such validity. This study evaluated the HR ability in estimating the ${\dot V_{{O_2}}}$ V ˙ O 2 during 5-m shuttle running at different speeds. Methods: ${\dot V_{{O_2}}}$ V ˙ O 2 and HR of 12 physically active young men were recorded during an incremental forward running (FW) protocol and a 5-m shuttle test at 50%, 60%, and 75% of maximal aerobic speed (MAS). Slope and intercept of the relationship between HR and ${\dot V_{{O_2}}}$ V ˙ O 2 (HR/ ${\dot V_{{O_2}}}$ V ˙ O 2 ) were individually determined, in both protocols. The HR measured during the shuttle test was used in the FW HR/ ${\dot V_{{O_2}}}$ V ˙ O 2 to estimate ${\dot V_{{O_2}}}$ V ˙ O 2 at each shuttle speed. A paired Student's t-test compared slopes and intercepts of the two HR/ ${\dot V_{{O_2}}}$ V ˙ O 2 . A two-way RM-ANOVA and an equality test examined, respectively, the differences and the equality between measured and estimated ${\dot V_{{O_2}}}$ V ˙ O 2 . Lastly, a Bland–Altman plot described the accuracy and precision of the estimated ${\dot V_{{O_2}}}$ V ˙ O 2 at each shuttle intensity. Results: Slopes and intercepts of the HR/ ${\dot V_{{O_2}}}$ V ˙ O 2 appeared not different between FW and shuttle running. At 50%MAS, HR underestimated the ${\dot V_{{O_2}}}$ V ˙ O 2 (~7%), whereas returned accurate values at the two higher velocities, although with high variability (±18%). Conclusions: When using HR as ${\dot V_{{O_2}}}$ V ˙ O 2 indicator during shuttle running over short paths, a separated analysis of the HR validity as ${\dot V_{{O_2}}}$ V ˙ O 2 indicator is recommended especially when administering different exercise intensities. [ABSTRACT FROM AUTHOR]

Cobalt- and nickel-based superalloys are being extensively used in aerospace, automotive and medical applications due to their specific properties, which include working at high temperatures and stresses, good corrosion and oxidation resistance. This paper incorporates a review on the machinability aspects of nickel- and cobalt-based superalloys in turning operations. The machinability aspects like tool wear and surface integrity are critically reviewed for turning operation. Also, the effect of parameters, such as coating, cooling methods, cutting speeds and feed rate on tool wear, is reviewed critically. The different tool wear mechanisms that occur during machining of these superalloys are studied along with surface integrity, which include surface roughness and microstructures. Lastly, conclusions drawn are based on parameters that need to be improved for sustainable machining of nickel- and cobalt-based superalloys. This review will guide researchers and manufacturers for proper understanding of parameters selection. [ABSTRACT FROM AUTHOR]

Flood lubrication is often replaced with minimal quantity lubrication (MQL) because of its eco-friendly properties. Surface smoothness, chip removal from cutting regions, improving the tool life, friction reduction at tool/work/chip tip, and temperature reduction during machining are all objectives of the lubricant. Nevertheless, choosing the correct cutting fluid for MQL is seen to be the most pressing issue, even if there are many factors to consider, such as industrial health concerns and environmental contamination. Tool wear, cutting temperature, and surface quality were the focus of this study on machining performance. The experimental settings consist of three machining conditions: oil MQL (OM), ionic liquid (IL) MQL, and LN2. Additionally, there are two various feed rates and three different cutting speeds. Results showed that compared to IL MQL and OM, using LN2 as a cooling medium dramatically reduced cutting temperature, surface roughness, and flank wear. All things considered, the waspaloy is best machined in an LN2 environment. [ABSTRACT FROM AUTHOR]

Recent research has mostly focused on replacing traditional lubricants with nanoparticle-based fluids to increase machining performance. The current work compares three distinct environmental conditions in turning of A286 alloy: oil machining (OM), nano Low Quantity Lubrication (nLQL), and LN2 (liquid nitrogen). Cutting speed (Vs), environment, and feed rate (f) were used as control parameters, with responses assessed in terms of flank wear (Vb), crater wear, surface roughness (Ra), machining temperature (Mt), and chip morphology. The L27 array was chosen for the testing runs. The experimental findings demonstrated that LN2 cooling significantly lowered Ra by 54% and 24%, Vb by 62% and 53%, and Mt by 45% and 73% when compared to the OM and nLQL settings. Under cryogenic circumstances, surface integrity was also enhanced. COPRAS, a multi-response optimization approach, was used to determine the best trials for picking the best outcomes. [ABSTRACT FROM AUTHOR]

The conventional turning (CT) of Mg-SiC was found difficult due to high tool wear and surface roughness, which reduced the machinability of the composites. In this paper, a study applying ultrasonic vibration assisted turning (UAT) along with minimum quantity lubrication (MQL) is proposed to improve the machinability of Mg-SiC. The input parameters used in this work are spindle speed (SS), feed rate (FR), depth of cut (DOC), and percentage intensity of ultrasonic power (PIUP). The flank wear morphology of the cutting tool and average surface roughness (Ra) of the workpiece is studied. In addition, the surface topography of machined samples was studied by AFM to assess the surface quality. The results show that UAT with MQL reduces the Ra by 21% and 7% compared to CT and UAT at dry cutting conditions. The flank wear (Vb) decreased by 15% compared to dry UAT. [ABSTRACT FROM AUTHOR]

Nowadays, productivity enhancement in machining operations in eco-friendly machining environment is a front-end requirement in the machining industries. In general, minimizing tool wear (Vb) and surface roughness (Ra) in machining processes can directly boost productivity. Therefore, the current effort attempts to improve productivity by regulating tool wear and surface roughness in an environmentally friendly machining environment. In this study, innovative textured tools (TT) were created, and the machinability performance of the produced tools was assessed under dry, conventional, and MQL conditions. According to the study's findings, MQL cooling with TT considerably reduced the cutting temperature (T), Vb, and Ra to maximum values of 13%, 17%, and 29%, respectively, over untextured tools (UT). In addition, it was shown that MQL cooling considerably enhanced turning performance in both tools compared to without cooling and conventional cooling, respectively. Additionally, chip morphology research was done and showed promise using textured tools in MQL conditions as opposed to other machining settings. [ABSTRACT FROM AUTHOR]

Amused with the blissful benefits of micro-textures, researchers consider it a promising option for improving cutting tool performance, especially during machining superalloys. Through this study, the machining performance of two homothetic and six hybrid micro-textured tungsten carbide inserts have been comparatively assessed while dry turning Inconel-718. Dimple and channel micro-textures were the two independent homothetic textures. Dimple and channel micro-textures with 0°, 45°, and 90° orientation angles and a combination of triangle, square, and dimples constituted six different hybrid micro-textures. Micro-textures were fabricated on the rake face of inserts using a Ti-sapphire fired, nanosecond pulsed, infrared fiber laser. Dimple and channel micro-textured tools at 90° texture angle on rake face performed exceptionally well. Improvements in average tool life, cutting forces, and surface finish have been reported. Adhesion and attrition were the predominant forms of tool wear. Chip morphology study revealed long helical and continuous but segmented chips. [ABSTRACT FROM AUTHOR]

Nitrogen strengthened austenitic stainless steels are uneasy to machine. 22-13-5 stainless steel better known as Nitronic-50 is also not an exception. The current study deals with such an investigation where Nitronic-50 has been machined under varied cutting speeds, feeds and depths of cut and its machinability has been tried to be adjudged on the basis of cutting forces, apparent coefficient of friction, tool-tip temperature, chip reduction coefficient, flank wear width, chip morphology and surface roughness. It is seen that while using higher cutting speed-lower feed-higher depth of cut combination, tangential cutting forces were 18.83% and 29.57%, apparent coefficient of friction was 9.48% and 12.90%, tool-tip temperature was 11.02% and 22.31%, flank wear was 41.25% and 29.91%, and surface roughness was 22.91% and 24.27% lesser as compared to the higher values obtained with higher cutting speed-higher feed-higher depth of cut and intermediate cutting speed-higher feed-higher depth of cut combinations, respectively. [ABSTRACT FROM AUTHOR]

17-4 precipitation hardening stainless steel is a recognized material with good strength and can overcome abrasion and corrosion resistance, which is frequently preferred in the situation of extreme pressure and high pressure. However, it is a tough-to-cut material due to its high ductility. Hence, it is necessary to obtain the optimal parameters for improving the machining performance of the 17-4 PH steel. In this research, the significance of the surfaces machined is analyzed with cutting temperature along with flank wear by changing turning input factors such as cutting speed, feed and machining conditions (dry, oil and ionic liquid (IL)) with low-quantity lubrication. The optimal solution was determined using response surface method. The outcomes reveal that environment outperforms other control parameters. IL is found to be an important factor in determining the responses. [ABSTRACT FROM AUTHOR]

High-speed turning of Inconel 718 has been assessed with coated carbide tooling incorporating the minutely explored eco-friendly cutting fluid as water vapour. Effect of total seven parameters, viz. nozzle diameter, stand-off distance, pressure, flowrate, cutting speed, feedrate and depth of cut, has been explored for the resulting machined surface quality in terms of surface roughness and surface alterations; additionally introspection of chip reduction ratio has been done to evaluate cooling/lubrication mechanics of water vapour at tool-work interface. The parameters of stand-off distance, cutting speed, feedrate and depth of cut were dominantly affecting the surface roughness with their contributions being 9.70%, 22.70%, 20.85% and 34.47% respectively. By increasing nozzle diameter, stand-off distance and pressure, around 13.28%, 16.47% and 8.82% reduction in surface roughness is possible respectively on account of enhancement of cooling and lubrication effect; however conversely increasing the cutting speed brought around 40% increment in surface roughness. [ABSTRACT FROM AUTHOR]

Recent research has focused on replacing traditional cutting fluids with nano-cutting fluids to enhance machining performance. Also, hybrid nano-cutting fluid composed of two or more types of nanoparticles has gained popularity. The aim of this study is to investigate the effect of the mixing ratio of Al2O3 (Alumina) and MWCNT (multiwall carbon nanotubes) nanoparticles blended in vegetable oil during the turning of stainless steel SS-304 with minimum quantity lubrication (MQL) cutting conditions. Two hybrid nano-cutting fluids with 1.5% weight concentration have been prepared using Al2O3 and MWCNT nanoparticles in the ratio of 80:20 and 60:40. The performance of hybrid nano-cutting fluids containing nanoparticles of both Al2O3 and MWCNT simultaneously has been compared with mono nano-cutting fluid containing only Al2O3 nanoparticles. Results show that use of hybrid nano-cutting fluid containing 20% and 40% MWCNT resulted in improvement in surface roughness of workpiece by 13.6% and 6.86%, respectively, over mono nano-cutting fluid. [ABSTRACT FROM AUTHOR]

Significant improvement in the design of ANN model has been hindered by the lack of evaluation of alternate model parameters. It is important that in generating a suitable ANN model, the best parameters capable of providing the fastest network and the most accurate test result be employed. In this study, the performance of the NN models based on the most suitable NN parameters such as the number of hidden layer neurons ranging from 2–20, activation functions; sigmoid (logsig), tangent sigmoid (tansig), and the linear (purelin), along with three different training algorithm (LM, SCG, and RP), has been evaluated to accurately predict the response values; metal removal rate (MRR) and tool wear in the turning operation of AISI 1050 steel bar. A great difference was observed in the performance of the activation functions and in the training algorithms. The optimal ANN model prediction, recorded R values of 0.827, 0.920 and 0.983 for the training, validation and testing sub-datasets respectively, while an overall R-value of 0.876 was obtained for the training process, signifying confirmation of the predictive ability of the model. The experiments demonstrate that the identification of the most suitable activation functions can lead to significant performance improvements without actually increasing the number of neurons. [ABSTRACT FROM AUTHOR]

The machining of Al alloy/SiC composites is still a challenge, because the hardness of SiC particles is approximately 2700HV, which is much higher than the hardness of most tool materials. Therefore, the tool wears out quickly. This reduces the tool life and increases the surface roughness of the components of the Al alloy/SiC composites. Hence, there is an urgent need to investigate the influence of SiC particles on tool wear during the turning of 7075Al alloy composites and quantification of flank and crater wear in turning of AA7075/SiC Composite. The experimental tests for turning AA7075/15 wt.% (20-40µm) SiC composite, using coated tungsten carbide tools were conducted. Efforts were made to determine how the cutting speed, feed, depth of cut, and nose radius affect the flank and crater wear of carbide inserts, while turning AA7075/15 wt. % SiC. The effect of the AA7075/15 wt. % SiC composite elements, on tool wear were found out. SiC particles may be removed from the AA7075 matrix, or they may remain in matrix, during machining. If the SiC particles are removed, the tool will not be damaged. If SiC particles remained in the matrix, they scratched the tool flank. This results in excessive tool-flank wear. The results showed that flank and crater wear increased sharply with increasing of depth of cut. SiC was the main element responsible for the wear of the inserts. The novelty of this work is that, so far, little research has been conducted on the influence of elements present in AA7075 Al alloy/SiC composite on the wear of carbide inserts. In this work, investigations were conducted on the effects of elements in AA7075/15 wt. % SiC composite on wear of carbide inserts while machining of AA7075/SiC composites. Measures to minimize tool wear have also been reported. Wear of inserts due to presence of SiC particles in AA7075/15 wt. % SiC composite has been considerably reduced by using carbide inserts coated with titanium nitride (TiN). [ABSTRACT FROM AUTHOR]

Surface roughness is primarily used to evaluate the surface finish of a workpiece, which significantly affects the quality performance of the finished components. Effective surface roughness prediction can reduce the time of trial-and-test, thus increasing productivity and reducing costs. Although earlier studies have proposed many different prediction approaches for different machining methods, few studies have been done to develop a generic approach for surface roughness prediction. Therefore, this paper presents a generic evolutionary ensemble learning (GEEL) framework for surface roughness prediction of different kinds of manufacturing process. The GEEL framework for surface roughness prediction consists of three modules, including pre-processing module, multi-algorithm regression module, and GA-based ensemble learning module. Validation experiments were conducted on fluid jet polishing (FJP) of 3D-printed Cobalt Chrome (CoCr) alloy and other seven cases of different machining methods. The results indicate that the mean square error (MSE) and mean absolute error (MAE), obtained by the proposed method were reduced to a certain extent than typical methods in predicting the surface roughness, exhibiting excellent prediction performance and robustness. At the same time, the method has good extensibility and is expected to become a generic framework for surface roughness prediction in manufacturing. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to investigate the effect of combined turning and balance training on ground reaction force (GRF) characteristics during walking and turning in older men.Methods: Thirty older men were selected and randomly divided into two equal experimental (EG: age = 65.47 ± 2.50 years; BMI = 24.57 ± 0.68 kg/m2) and control (CG: age = 65.80 ± 2.34 years; BMI = 24.72 ± 0.64 kg/m2) groups. EG participants completed 12 weeks of training. Kinetic data were recorded using the force plate.Results: After the training, there was a significant difference between the EG and CG in the peak of GRF components and related time parameters as well as the required coefficient of friction in all directions. There was a significant decrease and increase in the stance time and loading rate respectively after the training in EG.Conclusions: The results showed improvement in gait and turning performance of older men. Therefore, combined exercises with emphasis on the turning components for older men are recommended. [ABSTRACT FROM AUTHOR]

In the machining of difficult-to-machine metals, such as titanium-based alloys, the delivery of coolant with high pressure can increase machining efficiency and improve process stability through more efficient chip breaking and better cooling. Proper selection of machining conditions can also increase the productivity of the process by reducing cutting forces and tool wear rate. To investigate the effect of high-pressure jet cooling (HPJC) on cutting force, surface roughness, and chip formation of Ti-6Al-4V ELI in high-speed turning, Grade 5 Ti ELI turning tests were carried out under coolant pressure of 200 bar. A lower pressure of 6 bar was also used in this study to compare the results of the pressure change. In general, surface roughness increased as the feed rate increased at constant cutting speeds in experiments with both 6 bar and 200 bar coolant pressures. Even though 200 bar pressure provided a better cooling thus reduced cutting force, and tool wear rate; the surface roughness values ​​obtained from the experiments with 200 bar were relatively worse than the experiments with 6 bar pressure. It was also seen that 200 bar coolant pressure may result in instabilities in the turning process in terms of chip geometries and formations. [ABSTRACT FROM AUTHOR]

Even though metal may be effectively shaped by a variety of other manufacturing techniques, machining continues to play a significant role in industries. Turning is a conventional chip-forming operation that removes undesirable or surplus material from a cylindrical workpiece. The major objective of process optimization in turning operation research is focusing on the development of statistical modeling and optimization techniques for boosting production rate, lowering costs, and reducing product rejection. The current work aims to improve the CNC turning process of Al 7075 using coated carbide inserts. This investigation uses grey relational analysis, desirability function analysis, Multi-objective Genetic Algorithm (MOGA) and Multi-objective Genetic Particle Swarm Optimization (MOPSO) to optimize factors to minimize responses like surface roughness and cutting force. Comparative evaluation of results of optimum input parameter sets results in close agreement, both in traditional optimization and metaheuristic-based optimization. In particular, MOGA is found to be more efficient to solve this stated multi-criterion decision-making problem as compared to other methods. [ABSTRACT FROM AUTHOR]

In this investigation, commercially pure titanium (grade2) was machined under cryogenic conditions at high cutting speeds with varying feed rates and depths of cuts. A Taguchi orthogonal array is used to choose the cutting parameters. The output responses include experimentally confirmed cutting forces (Vc), surface roughness (Ra), tool wears, chip production, and chip shape. In order to obtain the final significant machinability, an excellent parametric combination for the work section was obtained by GRA. ANOVA was used to estimate the percentage contributions of the control components. Finally, the cryogenic liquid significantly lowers the cutting temperatures even at high cutting speeds, producing chips with favorable serrations. [ABSTRACT FROM AUTHOR]

In the engineering world, the machining of advanced materials like titanium alloys, which is having their superior applications in a variety of domains, that is, bio-implants, biomedical, aerospace, and so on, has been a challenge for many decades to the researchers. The optimised surface topography for such alloys has been revealed as a function of various input parameters. In this study, an attempt has been made by conducting the experimental investigation on the surface integrity and the quality machined work surface in turning of titanium alloy, that is, Ti6Al4V through employing cryogenically treated and non-cryogenically processed CBN inserts. The surface quality and the integrity of processed titanium alloy work-surface have been investigated under the influence of various considered input factors. The design of experimentation was constructed for planning the experiments. The analysis of variance test has been attempted for the studied response, that is, surface roughness and the mathematical models for the studied surface roughness (with both CBN inserts; cryogenically and non-cryogenically treated) have also been developed. The attained optimised parametric conditions for surface roughness are; feed rate – 0.067 mm/rev, cutting speed – 63.852 m/min, and depth of cut – 0.526 mm; and feed rate – 0.066 mm/rev, cutting speed – 59.450 m/min, and depth of cut – 0.309 mm, for non-cryogenically and cryogenically treated CBN inserts, respectively. Artificial neural network (ANN)-based modelling has also been attempted to predict and analyse the dataset of experiments. There is a variation of 1.43% between ANN predicted data of NC CBN and NC CBN experimental data. Further, there is an error of 0.2% between ANN predicted data of Cryo-CBN and Cryo-CBN experimental data. The microstructure analysis of the turned titanium surface reflected the presence of few tearing and groove lines with both the CBN inserts employed. The scratches and bamboo lines have been due to the built-up edges produced in the inserts. [ABSTRACT FROM AUTHOR]

In this study, the effects of casting modifiers on the surface roughness and chip formation of Al-12Si alloy materials were experimentally investigated. Machinability tests were carried out using a conventional lathe. Machinability tests were performed on four different materials, Etial 140, Etial 140 +CuSn5, Etial 140 +Al10Sr and Etial 140 +Al10Sr+CuSn5, respectively. A constant depth of cut, 3 different cutting speeds (Vc: 35, 95, 135 m/min) and three different feed rates (f: 0.08, 0.16, and 0.32 mm/rev) were chosen as test parameters. The most effective roughness reduction under these test conditions was 7.21% for the Al10Sr modified test material. According to the measured density values of the unmodified material, the density values of the other tested materials increased by 1.65% for CuSn5, 0.40% for Al10Sr and 1.16% for CuSn5+Al10Sr. Furthermore, the hardness values increased by 5.48% for CuSn5, 0.58% for Al10Sr, and 15.75% for CuSn5+Al10Sr. [ABSTRACT FROM AUTHOR]

For decades many models of orthogonal cutting have been developed with limited practical application. In the scope of Industry 4.0, a need is felt to develop models of practical machining operations, like turning, milling, and drilling. This research work contributes for the development of reliable 3D models of practical machining operations by proposing a model of turning using a constitutive model considering the effects of the state of stress and strain-rate on the elasto-viscoplastic and damage behaviors of Ti-6Al-4V alloy. The accuracy of the 3D turning model was evaluated by comparing the predicted machining outcomes (forces, chip thickness, residual stresses, and thickness of strain-hardened layer) with those obtained experimentally. The model can predict quite well the cutting force but underestimate the feed force. The predicted residual stresses match reasonably well the experimental ones in both circumferential and axial direction, and the simulated thicknesses of strain hardened layer were close to the experimental ones. ANOVA permitted to investigate the influence of the cutting conditions on the thermomechanical phenomena and surface integrity. Suggestions to improve 3D models of practical machining operations are proposed. [ABSTRACT FROM AUTHOR]

Elastomers are the class of materials that are widely used in a variety of industrial, commercial, and consumer applications due to their unique mechanical properties, including high elasticity, high flexibility, and high resilience. However, there are many challenges in machining of elastomers such as poor surface finish, build up of heat, degradation of elastomers, etc. To overcome these challenges, cryogenic cooling assistance has been introduced as a means of improving the machinability of elastomers. This paper presents a soft computing approach for optimizing the surface roughness and cutting force during turning of elastomers under different lubrication conditions. Three types of elastomers, namely Nitrile Rubber (NBR), Polyurethane Rubber (PU), and Neoprene Rubber (CR), are studied, and a cryogenic fluid delivery system is employed to improve the machining process. Taguchi's L27 array is used to vary the input parameters, and a Back-Propagation Artificial Neural Network (BPANN) model is developed to predict the cutting force and surface roughness. The cutting force and surface roughness are analyzed under different cooling conditions, cutting speeds, feeds, and depths of cut for various elastomers. The results show that changes in cutting conditions significantly affect the cutting force and that the type of lubrication used affects the cutting force by altering the material's physical properties. Cutting force is significantly influenced by cutting conditions, and NBR requires the highest cutting force compared to PU and CR. Further, at a cutting speed of 55 m/min, a feed of 0.11 mm/rev, and a depth of cut of 0.25 mm, the cutting force for NBR (85.1 N), while for PU (75.1 N) and CR (80.3 N), respectively. Finally, with LN2 lubrication conditions, the Cutting Force decreased by 45% and Surface Roughness decreased by 16.9%. This study provides insights into the factors affecting the elastomer machining process, which can be useful for optimizing the machining process parameters and improving machining efficiency. [ABSTRACT FROM AUTHOR]

Martensitic stainless steels are extensively used in aerospace, medical, and oil and gas industries because of their superior properties such as high hardness, strength, and corrosion resistance properties. However, the machining of this work material becomes difficult due to its high hardness and low thermal conductivity leading to high cutting force requirements and tool wear. Recently, the application of structured tools is one of the sustainable machining techniques used to enhance the machinability of work materials. Most of the researchers have studied only the influence of conventional structured geometries and have mainly concentrated on experiments. But the conduction of experiments involves bulky and costly experimental setups and also consumes a lot of time. Also, the bio-mimicked geometrical shapes and various geometrical parameters of structured tools on machining characteristics of martensitic AISI 420 steel have not been studied. Therefore finite element (FE) modeling proves to be a beneficial technique as it saves time and effort. In the current investigation, a 3D FE model is developed to examine performance of different geometrical structured tools in improving the machinability of AISI 420 steel. Johnson cook (JC) material model is utilized for modeling workpiece. Initially, the tangential force results obtained through simulation are validated with tangential forces obtained through experiments with an error of 6.65% using conventional tool and 5.57% using bio-mimicked structured tool, indicating the suitability of the machining model. Further, the effect of various structure shapes, mainly bio-mimicked crescent structure, dimple structure, and groove structure, was studied, and it is noticed that crescent-structured tool depicted better performances in lowering cutting force, effective stress, and cutting temperature. After getting superior geometry, i.e., crescent-structured geometry, the influence of variation in crescent structure parameters (radius, edge distance) was examined to study its influence on the above-mentioned machining responses. The variation in structure parameters significantly influences various output responses, indicating that bio-mimicked structured tools have a lot of potential to improve the machining performance of AISI 420 steel. [ABSTRACT FROM AUTHOR]

Dry machining is becoming increasingly popular due to concern regarding the safety of the environment. This research-cum-review article presents a novel technique for identifying unknown grades of aluminum alloy and brass workpieces (since the supplier did not provide the alloy details) by dry turning experimentation and logic; this paper also comparatively analyzes the resulting cutting forces and power. Dry turning experiments have been conducted on aluminum alloy and brass workpieces at a feed of 0.04 mm/rev and a cutting speed of 42 m/min. Turning was performed at depths of cut (DOC) of 0.5, 1.0, and 1.5 mm with an HSS cutting tool by use of a center lathe. The determination of the cutting forces involved the use of a dynamometer linked with a computer facilitated with the LABVIEW software package. The resulting DAQ output has been analyzed to calculate cutting forces and power at various DOC. The resulting machining data are compared with literature for a range of aluminum alloys and brasses. Logic philosophy has been applied to identify the workpiece alloys grades based on specific cutting energies. [ABSTRACT FROM AUTHOR]

Hybrid machining processes are developed to achieve enhanced machining performance for various materials. In this study, ultrasonic vibration and laser sources interact simultaneously during the hybrid turning process and the process is termed ultrasonic vibration laser-assisted turning (UVLAT). Ultrasonic vibration-assisted turning (UVAT) fixture is mounted along with laser assisted turning (LAT) fixture on the lathe machine during the developed hybrid process. An experimental investigation on aluminum 3003 alloy is performed to analyze the machining performance for conventional turning (CT), UVAT, LAT, and UVLAT. Cutting speed and laser power are varied to machine aluminum alloy during various processes. The investigation shows that lower machining forces, higher machining temperature, smooth and lesser segmented chips, and lower surface roughness are obtained during UVLAT in comparison to CT, UVAT, and LAT. At higher cutting speed, machining forces and surface roughness are increased and decreased at higher laser power, whereas vice versa to machining temperature with variation in speed and power. Smooth edges and less segmentation are observed at higher laser power and cutting speed. Outcomes suggest that the machining performance of aluminum alloy is enhanced during the UVLAT process when compared with other processes. [ABSTRACT FROM AUTHOR]

Cutting tool performance plays a key role in various machining sectors because of its significant impact on production cost, product quality, and cutting tool life. A comprehensive evaluation of machinability characteristics offered a better way of selecting the proper cutting tool and cutting velocity to enhance the product quality. To establish a relationship between variation in medium ranges of cutting velocity to temperature, force, surface finish, and chip morphology affect the machining of Monel alloy 400, a hard-to-machine material, determining coated TiAlN carbide cutting tool performance. This work investigates the comparative cutting performance of tungsten carbide cutting inserts (uncoated and TiAlN coated) during the turning of Monel alloy 400 under dry condition at varying cutting velocities. Cutting force, cutting temperature, surface quality parameter, and chip morphology have been determined to correlate with tool wear for varied cutting velocity to reason out cutting tool performance. EDS analysis on the worn tool was investigated to identify the tool's wear-related mechanisms under various cutting conditions. Coated TiAlN tools have a lower cutting zone temperature and cutting force than uncoated tools, which leads to better surface quality and less insert wear with cutting velocity. [ABSTRACT FROM AUTHOR]

Industries have been pursuing a competent machining strategy that fulfills the necessity of sustainability without deteriorating tool wear or final product quality of components made from difficult-to-cut material Titanium 64. This article attempts a combination ultrasonic vibration with vegetable oil-based cutting fluid (VCF), to increases the tool life and machinability of Titanium 64. In-house developed Ultrasonic-assisted turning (UAT) setup for vibration, and emulsion of 10% Canola oil for cooling, are used. The machinability in respect of cutting and feed force, tool-chip contact length, and flank and crater wear, are examined. As a result, the UAT under VCF offers a reduction in tool-chip contact length by 12–45%, cutting force by 10–25%, and feed force by 20–40%. Moreover, ultrasonic-assisted turning using vegetable oil-based cutting fluid also decreases the adhesion and abrasion wear from the rake face, which is obvious in the conventional turning process of Titanium 64. [ABSTRACT FROM AUTHOR]

Minimum quantity lubrication (MQL) is widely preferred over flood lubrication due to its environmental-friendly nature. The objective of the lubricant is to enhance the surface finish, eliminate the chips from the cutting areas, improves the tool life, reduces friction at the tool-work and tool-chip interfaces and also reduces the temperature in machining. However, the choice of proper cutting fluid in MQL is considered as the primary issue to be resolved while considering various factors like environmental pollution and industrial health risk. In this study, the machining performances such as surface quality and tool wear were examined. The experimental parameters include three machining conditions such as (a) dry, (b) oil MQL and (c) ionic liquid (IL) MQL under three different feed rate and cutting speed. The results confirm that IL MQL relatively reduces wear on the tool and surface roughness than under dry and oil MQL conditions. [ABSTRACT FROM AUTHOR]

Due to their increased hardness, hardened steels are referred to as difficult-to-cut metals. Machining such hardened steels (hard machining) is preferred since it minimizes process stages and processing time. However, severe machining in dry conditions needs larger specific energy for metal removal, reducing tool life dramatically at higher velocities which affect the product quality as well. Cutting fluids influence machinability through cooling, lubricating, and washing away chips. Excessive usage of cutting fluids harms the environment, economy, and operators' health. Researchers are so focusing on MQL as a sustainable green cooling alternative to potentially damaging conventional cooling approaches.In this current work, MQL was initially introduced with its core ideas and functions. As a follow-up, the application of MQL in various machining techniques especially for hardened steel was discussed. A complete evaluation of the various modes of MQL was presented, along with its advantages and disadvantages. According to studies, using NFs as a coolant and lubricant has grown more popular than any other way due to its superior performance in temperature control, improved surface quality, and low environmental threat. Finally, this article provides easy-to-follow instructions on how to use MQL in various ways to improve the machinability of hardened steel. [ABSTRACT FROM AUTHOR]

This study focussed on the multi-response optimisation of turning process using an easier and accurate hybrid approach namely Taguchi-PCA-Utility approach. Turning of alloy steel under dry and LN2-assisted cryogenic cooling with two different geometry-shaped uncoated carbide inserts was carried out based on suitable design of experiments (Taguchi L16 orthogonal array). Five vital responses in turning such as temperature, roughness, feed force, cutting force and MRR were measured by varying the input factors (speed, feed, cutting condition and cutting inserts type). Principal component analysis (PCA) for relative weight calculation of responses and utility concept for deriving out the unified process index were followed. The optimum parameter settings for maximum utility value were found at 134 m/min speed with 0.12 mm/rev feed rate under cryogenic cooling using SNMG 120408-type cutting insert. Finally, in order to verifying the significance of proposed approach validation tests were conducted. [ABSTRACT FROM AUTHOR]

Magnesium alloys generate harmful emissions while using coolants during the machining process and it affects both the operator and the environment. Ultrasonic vibration assisted turning (UVAT) is an eco-friendly and advanced machining process to machine various materials than conventional turning (CT). In this study, experimental analysis is carried out to investigate the machinability of the magnesium AZ31B alloy during CT and UVAT processes. The effect of cutting speed during the processing of magnesium AZ31B alloy is analyzed and compared with CT in terms of machining forces, machining temperature, tool wear, chip morphology, surface roughness, microstructure, and microhardness. Results showed that compared with CT, machining forces and surface roughness is reduced significantly in UVAT. However, higher machining temperature is obtained during UVAT than CT. Flank wear is observed during CT although negligible tool wear is observed for UVAT. Chip segmentation is obtained for both CT and UVAT whereas higher chip thickness is observed for UVAT than CT process. Finer grains and higher microhardness are obtained in UVAT than the coarse grains and lower microhardness in CT. The results showed that the processing of magnesium AZ31B alloy during the UVAT process leads to enhanced machining performance compared to the CT process. [ABSTRACT FROM AUTHOR]

During cutting operations, cutting fluids increase heat carrying capacity from the cutting area and reduce friction at the chip-tool interface. It also offers benefits like favorable chip form, enhancement in the finish of product and tool life, lower cutting forces and power consumption during any cutting operations. But the inadequate application of cutting fluids and disposal creates several technical and environmental problems. So, due to the high demand for proper cooling and lubrication, many researchers are keen on cooling using cryogenic fluids. In this, liquid nitrogen is recognized as an effective cooling agent and a better lubricant as a cutting fluid during cutting. Beneficial outcomes are reduced insert wear rate, machined surface roughness, machining forces, power consumption, enhanced tool life and favorable form of chips with liquid nitrogen cooling through controlling the temperature at heat generation zones and thereby reduced adhesion at inter surfaces. This paper reviews the various cryogenic cooling approaches using liquid nitrogen during turning Ti-6Al-4V alloy. The features of existing liquid nitrogen approaches are compared based on the machining performance, and directions for further research are recommended. [ABSTRACT FROM AUTHOR]

Focusing on the philosophical puzzle of time and its relation with being and presence the paper explores the volatile relationalities un/tying them in shaping our conceptualisation of memory as re-turning. With such an approach the paper analyses the paradoxes that always haunt any attempt at thinking time, being and presence in their specificity as well as within their general embrace. It is through such play of the specific and general, the paper submits, that the thinking of memory and its acts of re-turning comes to be conceptualised in terms of linear, teleological, homogenous understanding of continuity. Turning towards Bergson and Heidegger's approaches to the question of time, presence and being the paper attempts to open-up the layered paradoxes that not only shape any act of turning but also the thinking of possible itself as a general category for conceptualising memory as re-turning. Bringing in the question of language and its ontological and temporal concerns, the paper thus brings in the concept of "poetics" to hint at the continuous negotiation that thinking of such interstices in language demands. It is towards such contingencies of the (un)timely, the paper submits, that any attempt at thinking memory as re-turning gestures. [ABSTRACT FROM AUTHOR]

To improve the quality of the product produced considering productivity, it is important to evaluate the factors affecting the machining experimentally and analytically. Looking at the harmful effects of conventional cutting fluid on the environment and workers' health, in the current research work effort has been made to explore the effectiveness of minimum quantity lubrication (MQL) and solid lubricant in machining. Micron-sized calcium fluoride (CaF2) solid lubricant powder particles are mixed in SAE 40 cutting oil and applied to the machining area with minimum quantity lubrication. The effect of different particle sizes and wt% of CaF2 has been analysed by measuring surface roughness, chip-tool interface temperature, flank wear of the tool, and cutting forces. Results demonstrated that the smaller size and 20 wt% of CaF2 powder have improved the process performance by lowering surface roughness and tool wear. The effectiveness of solid lubricant can be viewed as an alternative compared to wet machining. The results can be used by related industries to improve machining performance with the use of MQL and solid lubricants leading towards clean and sustainable manufacturing. [ABSTRACT FROM AUTHOR]

In machining operations, the application of cutting fluids has been of prime importance for the extraction of heat from rake surfaces, ease of removal of the chips and reduction of friction at the chip–tool interface. These three objectives are achieved by the supply of suitable conventional cutting fluid at the machining zone using different techniques. However, the misuse of these fluids and their wrong disposal methods were found to have an adverse effect on the environment and health of human. To reduce the usage of conventional cutting fluid, minimum quantity lubrication (MQL) technique has been emerged as an alternative means in the last few years, leading to better eco-friendly. Further, to increase the sustainability of MQL technique, it becomes necessary to use an appropriate exceptional nanostructured material with MQL that could be an effective cutting fluid (i.e. nanocutting fluids) with better tribological and thermophysical properties, and might be helpful in addressing the eco-friendly problem to a great extent. Therefore, the present paper focuses on the review of important published works related to the use of mono/hybrid nanocutting fluids with MQL technique at various processing parameters in different metal cutting operations. Most of the studies have shown a significant reduction in cutting forces, temperature at cutting zone, tool wear, and friction coefficient, and considerable improvement in surface quality by the addition of mono/hybrid nanoparticles enriched cutting fluid in MQL technique as compared to dry as well as wet machining processes. Further, the paper discusses the future scope in the area of hybrid nano-cutting fluids in different machining processes. [ABSTRACT FROM AUTHOR]

Manufacturing cost and productivity in machining systems can be significantly affected by the optimized input sources. Further, metal cutting industries have shown curiosity toward surface textured tools due to gain in productivity. In this context, new textured tools were developed and machinability studies were carried out on AISI 304 material under eco-friendly technique namely Minimum Quantity Lubrication (MQL) with so developed tools. The novel textured tools were fabricated by making circular micro pit holes on the rake face of the tungsten carbide tool using laser technology. In this work, a new weighted gray relation analysis (WGRA) integrated Jaya algorithm is proposed to determine the best cutting parameters. From the result, it is found that 54%, 7% respective reduction in surface roughness (Ra) and tool wear (Vb) and 27% increment in material removal rate (MRR) at the optimum conditions determined by the proposed optimization technique. It is concluded that the proposed work meets the environmental sustainability requirements and improved the turning process performance. [ABSTRACT FROM AUTHOR]

Advanced machining has become one of the inevitable processes for the fabrication of miniature industrial components that demands high dimensional accuracy. Magnesium (Mg) and its composites have widespread applications in the areas of aerospace, medical, and automobile sectors. The objective of this work is to analyze the machinability of Mg—rare earth (RE) alloy (Mg3Al2.5La)-based nanocomposites using wire electrical discharge turning (WEDT), a variant of EDM process. Y2O3 (0.6 and 1.9%) reinforced magnesium composites are prepared through disintegrated melt deposition technique. SEM and XRD analyses confirmed the intermetallic phase formation, such as Al11La3, and Al2La. Machining experiments are conducted with input parameters: discharge ON time, wire feed and spindle rotational speed each varied at three levels to study surface roughness (Ra) and volume of material removed (MRR). Results showed that Ra of the machined samples increases and MRR decreases, with the increase in % reinforcement and discharge ON time. The lower Ra value of 2.985 µm and higher MRR of 34.85 mm3/min are observed for the Mg3Al2.5La sample. This result is attributed to the absence of particle pullout and increased thermal conductivity of magnesium alloy during machining. Prediction analysis based on mean values is carried out to confirm the accuracy of the experimental results at optimal parametric levels. [ABSTRACT FROM AUTHOR]

High tool wear, poor product quality, and environmental damage are the outcomes during conventional machining of AISI 316 material with the conventional cutting tool. To minimize these decremental effects, textured tools were developed in the present work and machinability studies were conducted on AISI316 with developed tools under dry and Minimum Quantity Lubrication (MQL) environment. In the present work, single pattern textured tools (T-1 tool) and hybrid pattern textured tools (T-2 tool) were fabricated using laser technology. From the present study, paramount results were found in the MQL condition with textured tools over the dry condition. However, the T-2 tool considerably reduced the cutting temperature (Tc), tool flank wear (Vb), and surface roughness (Ra) to a maximum of 18, 9, and 36% respectively over the T-1 tool under MQL condition. The proposed hybrid textured tools under MQL are a promising technique meeting the demand of higher productivity and sustainability associated with environment and coolant cost. [ABSTRACT FROM AUTHOR]

Surface modification on the cutting tools (textured tools) emerged as an efficient machining technique that engages high productivity and avoids the cost associated with coolants. However, textured tools performance is significantly influenced by the type of texture design and geometry of the texture. Moreover, more research is available only on the performance of single pattern textured pattern tools. In this context, the novel hybrid textured tools were fabricated in the present research and investigated its cutting mechanism in turning of 17–4 precipitated hardened stainless steel (PH SS) materials under dry and conventional method (flood) cooling conditions respectively. Results of the current study indicate that hybrid textured tools under conventional cooling significantly minimized the cutting zone temperature (T), tool wear and surface roughness (Ra) to a maximum of 43%, 42% and 45%, respectively, over the dry cutting conditions. Further, tool wear analysis revealed that adhesion wear mechanism was observed in hybrid textured tools under both dry and wet cooling conditions, respectively. Furthermore, favorable chips were observed in hybrid tools under conventional cooling conditions that resulted in low cutting temperatures. As a whole, microgrooves act as lubrication storage sites. [ABSTRACT FROM AUTHOR]

Hard turning process, frequently used to finish the rotational surfaces of hard steel components, has some major issues like a high tool wear rate coupled with the degradation of surface finish and generation of brittle white layer. Due to this, the process productivity also remains low. In an attempt to improve the cutting tool productivity while machining hardened EN31 steel, uncoated ceramic inserts were used with the Minimum Quantity Lubrication (MQL) environment, which resulted in significant wear reduction on the ceramic inserts along with a better surface finish than that produced with a dry cutting. The most suitable process parameters, to produce an efficient cut, i.e., high process performance on both wear and surface finish fronts, were proposed. The surface integrity produced within the process parameter window identified was compared for both dry and MQL environments. It was confirmed that application of MQL brought about a significant reduction in formation of subsurface white layer both at lower and higher feeds (around 40% and 16.5% respectively) when compared to dry mode cutting. MQL condition enhanced the overall productivity of ceramic inserts with lower flank wear and better surface characteristics even at higher feeds, while at the same time, producing a thinner white layer. [ABSTRACT FROM AUTHOR]

In this research, the effect of ultrasonic vibrations in the turning process on geometric tolerances has been investigated. This has always been one of the most important challenges in the production of high-quality and precision parts. One of the important applications of the turning process is making parts with high dimensional accuracy. In this study, by applying ultrasonic vibrations to different machining parameters, we investigated the surface quality, runout, total runout, and straightness tolerance of a 2024-T6 aluminum workpiece. In the second stage, the effect of the presence of ultrasonic vibrations was investigated. The full factorial experiment design method was used, and 18 experiments were performed with this method. After that, the results were analyzed, and they are as follows. Compared to other machining parameters, the cutting speed has the highest effect on the runout, total runout, straightness tolerance, and surface roughness. Ultrasonic vibrations reduce all four output parameters of runout, total runout, straightness tolerance, and surface roughness. In particular, the surface roughness in ultrasonic turning decreased compared to conventional turning. Also, the formation of chips was investigated. This technique is suitable in manufacturing industries that require high dimensional accuracy. [ABSTRACT FROM AUTHOR]

Textured cutting insert filled with solid lubricants is one of the best alternative cooling methods in metal cutting industries. The problem associated with textured insert is the supply of solid lubricant and its continuity in flow while machining. In this work, an attempt is made on experimental investigation of supply methodology of solid lubricant to the textured inserts during turning process. Three different types of supply methodologies (paste form, liquid form, and soft coated form) are investigated. Performance of micro-hole textured inserts with tungsten disulfide (WS2) solid lubricant are conducted. The effect of control factors on an average surface roughness (Ra) using different solid lubrication supply is investigated. Analysis of Variance (ANOVA) method is applied for the estimation of significance. The results of the study reveal that the soft coated solid lubricant to the textured insert is performed better than the other methodology used for supplying of solid lubricant. Supply methods of solid lubricant with micro-grooved inserts are investigated for promoting dry turning process. This work eliminates difficulty in supply mode of solid lubricant to the cutting zone. Soft coated textured inserts are noticed significant advantageous of uniform spread, additional storage, and supply. [ABSTRACT FROM AUTHOR]

Some shortages in conventional flood cooling technique under heavy cutting settings were noted while machining. Therefore, nanofluids (NF's) that have elevated thermal conductivity than traditional cutting fluids are initiated to use in the mist system. In this investigation, aluminum oxide (Al2O3) nanofluid was employed in the minimum quantity lubrication (MQL) system for face turning of Incoloy 800. Variable feed-speed combinations were selected for the experimental design to examine the act of NF's under numerous cutting variables to determine the effect of NF with and without MQL machining. Ultimately, Al2O3 concentration offers an enhancement in tool life compared to other cooling strategies. Abrasion was noticed under all cutting strategies and it is less under NF with MQL. The desirability function was deployed to give the ideal machining setting by multi-criterion optimization. [ABSTRACT FROM AUTHOR]

Cutting fluids are generally used for lubrication and cooling the machined surface during the turning operation. The petroleum-based oil, when used for the machining process, has raised many health and environmental issues. The use of bio oils during machining process results in environmental-friendly working atmosphere, with minimal health hazardous among workers. Many researchers have worked on the effect of process parameters, surface characteristics of the machined surface by using bio oils as lubricants. The metallurgical transformation takes place on the machined surface during the machined surface. But the studies on using the bio oils on improving the machined surface, chip formation and generation of cutting force needs to be studied in details with comparison with other process methods. The change in the microstructure, during the machined process also needs to be studied thoroughly, where mere literatures are available. With this direction, the experimental studies were conducted to study the machining parameters during the turning process by using gingelly oil as cutting fluids. The studies showed that there was a gradual decrease in cutting force and improved surface finish on the machined part. The improvement in the machinability during the cutting process with respect to chip length, pitch and surface roughness was discussed for all the process. Finally, the changes in the microstructure on the metal surface for the different cutting forces were studied. [ABSTRACT FROM AUTHOR]

Inconel 718 superalloys are known materials with high applicability to components that demand exceptional chemical and mechanical properties at higher working temperatures combined with excellent surface finish requirements. However, due to the lack of in-depth knowledge regarding its machining process, the material is considered a difficult-to-machine material. Therefore, to improve the machining process of the Inconel 718 superalloy, by finding the optimal processing conditions, it was necessary to analyze the influence of the cutting parameters on the workpiece surface quality. In this work, the evaluation of quality indicators was made through the influence analysis of cutting speed, feed, tool, and lubrication parameters. The surface roughness (Ra, Rt), consumed power, vibration, and tool wear indicators were evaluated by following a Taguchi experimental design. To perform the machining process, the tool CNMG120408-M1 coating TS2500 with minimum quantity of lubricant was used. Results have proven that feed rate adjusted to 0.10 mm/rev and the cutting speed of 70 m/min provided the optimal processing results. It was observed that the feed increase led to an increase of all indicators. Consumed power denoted high sensibility concerning the machining parameters, suggesting its potential use in tool wear prediction studies applied for the Inconel 718 machining. [ABSTRACT FROM AUTHOR]

Most of the studies on cutting mechanisms and surface integrity in turning are investigated with a straight tool path (longitudinal/end face turning) while few contributions have been done in curved surface turning. This work explores the evolutions of cutting force, chip morphology and surface integrity when turning a curved surface, using fillet surface machining of AISI 304 stainless steel. The varying cutting conditions caused by the presented turning are revealed by detailed geometric analysis and employed as indicators for further discussions on cutting force, chip morphology, and machined surface integrity (including surface roughness, microhardness, microstructure, and residual stress). Apart from the difference of cutting force components in tangential, radial, and cutting speed directions along the fillet surface, wider and thinner chips are obtained from end face turning. The measured microhardness, microstructural alternation, and stress condition results comprehensively illustrate a reduction of severe plastic deformation from the outer face to the end face. [ABSTRACT FROM AUTHOR]

Micromachining is the essential technology for production of miniaturized parts and components, which plays a lot of roles in today's manufacturing technology with space limitations of products and economical aspects. In this investigation, response surface methodology with box-behnken design (BBD) is used to optimize the micro-turning parameters based on the relationships and interactions among the variables on tool wear. For conducting the experiment(s), three process parameters namely, cutting speed, feed, and depth of cut were considered and Titanium alloy is used as the base material with cermet insert. According to the design of matrix, totally 15 trials were conducted for different combinations of process parameters. The mathematical model is developed and as a role of process parameters, to calculate the output responses and the same were analyzed by using ANOVA with contour plots. In this paper, an investigation has been prepared for optimum machining conditions to produce the minimum tool wear 0.133 mm, and their optimized parameters cutting speed 3459 rpm, feed rate 7.4 µm/rev, with depth of cut 15 µm by 100% desirability. Among these optimal parameters, it minimizes the tool wear for the progress of tool life with suitability. [ABSTRACT FROM AUTHOR]