Feed Rate Research Articles

Experimental Investigation on the Machining Behaviour, Surface Integrity and Tool Wear Analysis in Environment Friendly Milling of Inconel 825

The study investigated end milling of Inconel 825 with varying spindle speed (N), feed rate (f) and axial depth of cut (da) with Minimum Quality Lubricant (MQL) and flooded lubrication. Molybdenum disulfide (MoS2) with the average particle size of 10 µm was used as lubricating agent. Work considered, center line average of roughness profile as a measure of surface roughness which was measured with a surface roughness tester. Material Removal Rate (MRR) was also measured experimentally using weight difference. The influence of spindle speed (N), feed rate (f) and axial depth of cut (da) during end milling of Inconel 825 on surface roughness and MRR were studied. Prediction of surface roughness by ANOVA linear model for MQL condition was found functionally adequate with R2 = 89.25% which fits with the experimental values. Also, the prediction and optimization of surface roughness using Response Surface Methodology (RSM) was proposed. It was found that, RSM model for MQL condition produced good agreement with the measurement of the given range of input cutting conditions with the prediction capability of 91.66%. Further, the machined surfaces and tool wear were analyzed using Scanning Electron Microscope (SEM) to understand the mechanisms of wear.

An Exploratory Study of the Surface Integrity of Various FRP Composites in Face Milling Operation

The use of glass, carbon and hybrid /glass/carbon epoxy polymer composites is widely used in the automotive, manufacturing and aerospace sectors. Milling is a secondary production process in which the final shape of the product is produced with the desired shape and high dimensional accuracy. The objective of this study is to enhance our knowledge of the machinability properties of composite materials in the secondary manufacturing industry. In this research study, performing face milling operations with different tools on bidirectional (BD) glass, unidirectional (UD) glass, carbon/epoxy, and glass/carbon/epoxy (hybrid epoxy) polymer composites. This experimental work derives conclusions that contribute to the improvement of the milling process for better surface quality. Taguchi’s L16 Design of Experiments (DOE) and Analysis of Variance (ANOVA) are used to determine the effect of tool type, speed of spindle, rate of feed, cut depth on surface roughness and delamination factor. And it was concluded that glass/carbon hybrid epoxy polymer laminates showed improved surface quality when milled with a Poly Crystalline Diamond (PCD) tool at parametric combinations of rate of feed is 300 mm/min, speed of spindle is 1000 rpm, and cutting depth is 0.5 mm. In addition, the experimental results of the scanning electron microscope examination were also verified. And found excellent machined surface quality and least damage with the above optimal process parameter combinations.

Cutting Force Modeling Considering Wiper Edge Cutting Effect During Face Milling of 316H Stainless Steel and Experimental Verification

Wiper tools are revered for their capacity to simultaneously achieve high-quality and high-efficient machining. Nonetheless, the cutting mechanism of wiper tools remains unclear, and the cutting force prediction model of wiper tools has not been reported, leading to severe wear of the bottom wiper edge and unstable cutting in machining processes. In this study, the cutting mechanism of wiper tools is systematically analyzed, and the mechanistic cutting force model considering the wiper edge cutting effect was established. The cutting force coefficients were calibrated by the cutting force separation method, which can quickly calibrate the cutting force coefficients for the flank cutting region dominated by the shear effect, the bottom cutting region dominated by the shear effect, and the bottom wiper region dominated by plough effect. Compared with measured cutting forces, the maximum average absolute errors in the predicted forces are 9.2 %, 7.6 %, and 9.3 % in the x, y, and z directions, respectively. Furthermore, the feed rate and the length of the wiper edge were primary determinants of the bottom-edge cutting forces. This study provides theoretical guidance and technical support for the wear mechanism and design of wiper tools.

Combining CFD and AI/ML Modeling to Improve the Performance of Polypropylene Fluidized Bed Reactors

Polypropylene is one of the most widely used polymers in various applications, ranging from packaging materials to automotive components. This paper proposes the Computational Fluid Dynamics (CFD) and AI/ML simulation of a polypropylene fluidized bed reactor to reduce reactor loss and facilitate process understanding. COMSOL Multiphysics 6.2® solves a 2D multiphase CFD model for the reactor’s complex gas–solid interactions and fluid flows. The model is compared to experimental results and shows excellent predictions of gas distribution, fluid velocity, and temperature gradients. Critical operating parameters like feed temperature, catalyst feed rate, and propylene inlet concentration are all tested to determine their impact on the single-pass conversion of the reactor. The simulation simulates their effects on polypropylene yield and reactor efficiency. It also combines CFD with artificial intelligence and machine learning (AI/ML) algorithms, like artificial neural networks (ANN), resulting in a powerful predictive tool for accurately predicting reactor metrics based on operating conditions. The multifaceted CFD-AI/ML tool provides deep insight into improving reactor design, and it also helps save computing time and resources, giving industrial polypropylene plant growth a considerable lift.

Shape Accuracy Improvement of the Flange Turning Process in Aluminum Aerosol Can Production

This study investigates the flange turning process in the production of aluminum aerosol bottles. Aluminum discs are lubricated, extruded, trimmed, washed, painted, and lacquered before undergoing necking, where flange turning ensures a secure, aesthetically pleasing fit. Errors in flange turning, such as uneven or tapered surfaces, can compromise bottle functionality and appearance. To address this, experiments were performed with different tool geometries, feed rates, and rotational speeds. The investigations aimed to achieve flat, consistent flange surfaces with minimal deviation from the desired geometry. Two main variables were examined: a 1 s waiting time at the end position and variations in feed rate and cutting depth. The waiting time improved flatness, halving surface deviations, while regrinding the tool reduced flatness errors to a tenth of the original values. Higher feed rates and speeds also enhanced surface quality, with flatness errors ranging from 371 μm to 75 μm. Overall, this study demonstrates that optimizing parameters like cutting angle, feed rate, and rotational speed, along with a waiting period, significantly enhances surface accuracy. These findings support more efficient production processes for aluminum aerosol bottles.

EFFECT OF DRILLING PARAMETERS ON THRUST FORCE AND DELAMINATION DAMAGE OF DRILLED RAMIE WOVEN – COIR FIBER HYBRID COMPOSITES

This study examines the effect of spindle speed and feed rate variations on the delamination mechanism and thrust force of hybrid composite materials reinforced with ramie weave and coir fibers. The specimen was made with a volume fraction of 30%, consisting of 6 layers of woven ramie, with the remainder being coir. The drilling process is divided into four main phases, showing changes in thrust force at each stage. The results indicate that an increase in feed rate tends to increase thrust force and cause microstructural damage such as delamination and fiber pull-out. At a feed rate of 0.26 mm/rev and a spindle speed of 1500 RPM, the maximum thrust force is reached, indicating the most severe damage. The delamination factor is higher on the exit side compared to the entry side, especially at higher spindle speeds. Tensile tests show a significant decrease in the tensile strength of the composite material due to drilling, with the highest tensile stress achieved at a spindle speed of 1500 RPM and a feed rate of 0.1 mm/rev, although still lower than the sample without holes. The combination of high feed rate and high spindle speed increases the risk of material damage, but the proper selection of drilling parameters can help minimize damage and maintain the mechanical integrity of the composite material. This study provides important insights for industrial applications where mechanical strength and drilling efficiency are crucial.

PENGARUH PARAMETER PEMESINAN TERHADAP KEKASARAN PERMUKAAN AI6061BE PADA PEMESINAN CNC MINI 500 WATT MENGGUNAKAN PAHAT KARBIDA STRAIGHT ENDMILL

The role of automatic machining with the help of computer programming such as Computer Numerically Controlled (CNC) has become commonplace today in both large and small industrial sectors or micro industry. CNC is a manufacturing process where previously programmed computer software is converted into code that can automate machining movements, one of which is the milling or lathe process. CNC performance is determined by machining output power. For micro industrial or laboratory scale, CNC with low power is usually used to cut soft materials such as wood, acrylic, aluminum and others. This is the basis for this research to look at the influence of machining parameters such as speed, depth of cut and feed rate on the surface roughness (Ra) of AI6061BE aluminum workpieces in the dry machining process on a mini CNC unit with a maximum spindle power of 500 watts. This research uses an experimental design based on the Taguchi method and takes the form of an L16 (43) orthogonal matrix. The chisel used is a Straight End Mill 2 fluke carbide chisel. The experiment was carried out 4 times cutting in the positive x-axis direction and 4 times in the negative x-axis direction for each variation of machining parameters. From the test results, surface roughness, feed rate is a parameter that is more influential than speed and depth of cut.

Multi-criteria decision making for evaluating a suitable MOO technique to improve the performance of AISI 1040 carbon steel and Ti-6Al-4V alloy

The objective of this work is to compare the machining performance of AISI 1040 Carbon Steel and Ti-6Al-4V alloy for a slot cutting operation using a 3-axis vertical milling machine. A set of 16 experiments was conducted, considering four factors: Feed rate, depth of cut, spindle speed, and coolant concentration, to remove material up to a finite depth. Three multi-objective optimization techniques namely, Grey Relational Analysis (GRA), Multi-Response Signal-to-Noise Ratio (MRSN Ratio), and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) were employed to determine the optimal machining conditions by maximizing the material removal rate and minimizing surface roughness and material hardness. It has been observed that the response performance index varies with different optimization techniques as well as different workpiece materials. The most significant contributions of each technique were evaluated through ANOVA analysis. A prediction model was developed using linear regression analysis. Finally, comparing the results of the three objective optimization techniques, GRA gives better performance than both TOPSIS and MRSN by effectively satisfying two objectives (i.e., maximizing material removal rate and minimizing surface roughness) for AISI 1040 Carbon Steel. In contrast, the MRSN technique provides better results than GRA and TOPSIS by effectively satisfying two objectives (i.e., maximizing material removal rate and minimizing material hardness) for Ti-6Al-4V alloy.

Study on the Effect of Laser Power on the Microstructure and Properties of Cladding Stellite 12 Coatings on H13 Steel.

To address the issue of cracking in aluminum extrusion dies during operation, this study employs laser cladding technology to modify the surface of these dies. This modification aims to enhance their hardness and friction resistance. Laser cladding technology was utilized to coat the surface of H13 steel with Stellite 12, a cobalt-based alloy, at varying laser power levels. The surface formation quality, microstructural organization, phase composition, microhardness, and wear resistance of the coatings were investigated using optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction (XRD), microhardness testing, and confocal microscopy. The results indicated that as the laser power increased, the surface formation quality of the coating gradually improved, while the dilution rate of the coating increased. Changes in the phase composition and microstructure were not significant, and both microhardness and wear resistance initially increased before decreasing. Optimal process parameters for achieving good surface formation quality, high microhardness, and strong wear resistance were found to be a laser output power of 2200 W, scanning speed of 10 mm/s, feeding rate of 1.2 r/min, and overlap rate of 40%. The results indicate that the coating applied to the surface of H13 steel using Stellite 12 enhances the performance of aluminum extrusion dies.

Performance Analysis of TiAlN/TiN PVD Coated Carbide Tools in High-Speed and Dry Machining of AISI 1070 Alloy Steel

This study investigates the performance of TiAlN/TiN PVD-coated carbide tools in high-speed, dry machining of AISI 1070 alloy steel. AISI 1070 is a high-carbon steel known for its exceptional hardness, making tool wear a significant challenge. The research focuses on evaluating tool wear, wear mechanisms, and optimal cutting parameters. Quantitative assessments of flank wear (VB) were conducted, alongside detailed Scanning Electron Microscopy (SEM) analyses to identify the primary wear mechanisms, such as abrasion and adhesion. The study determined that the optimal cutting conditions for minimal tool wear include a cutting speed of 231 m/min, a feed rate of 0.1 mm/rev, and a depth of cut of 1 mm. The TiAlN/TiN coatings significantly enhanced the tools' wear resistance and longevity, maintaining their cutting-edge sharpness under strenuous conditions. Additionally, the coatings effectively minimized the formation of white layers on the machined surface, preserving the mechanical properties and surface integrity of the alloy. These findings demonstrate the coatings' superiority in reducing friction and heat generation during high-speed machining. The study provides valuable insights for industrial applications, highlighting the potential of TiAlN/TiN-coated carbide tools to improve tool performance, operational efficiency, and overall productivity in high-speed machining environments.

A game-theoretic analysis for creative mid-roll ads on a content platform

The accessibility of pre-roll ads (PAs) has significantly diminished due to the privilege of skipping ads for paid members. Leading video platforms have introduced a new type of streaming ad, the creative mid-roll ad (CMA), which reduces consumer aversion to ads by tightly integrating them with video. Moreover, paid members are also a target group for CMAs, which may conflict with their interests and potentially reduce their viewing volume. We develop a game-theoretical model to examine the platform's advertising pricing and the advertiser's mode selection process. Counterintuitively, the CMA fee rate at equilibrium decreases as video attractiveness and the CMA's ad conversion ability increase because higher video attractiveness and ad conversion ability enhance the advantages of lowering the CMA fee rate. We find that the advertiser will balance conversion efficiency and price gaps between the two ad modes when making decisions. As increased conversion ability prompts advertisers to invest more, a significant gap in conversion efficiency results in higher equilibrium investment in PA mode compared to CMA mode. A low proportion of paid members results in a better consumer surplus in CMA mode than in PA mode, which is because the CMA mode targets paid members with its advertisements.

Performance Evaluation of the Melkassa-Made Engine-Driven Maize Sheller

The strategy of Ethiopian mechanization is to minimize postharvest loss. The methods of crop production were traditional. It involves high drudgery, low quality and quantity, time-consuming, and inefficient operation. To minimize loss, the sheller, thresher, and storage developed. But the performance was not clearly determined for researchers and manufacturers for selection and multiplication. The target of this research was the evaluation of Melkassa maize Sheller. It was conducted at three levels of feed rate: 7500, 6500, and 500 kg/hr., and speed: 700, 650, and 600 rpm. The moisture is 14 percent and maize LIMU variety. Split plot design of feed rate as the main factor and drum speed as a sub factor. The maximum shelling capacity of 6608.9 kg/h was achieved at a feed rate of 750 kg/h and a speed of 700 rpm. Where the minimum obtained at 5000 kg/hr and a speed of 600 rpm is 4242.27 kg/hr. The highest efficiency was 99.9 percent, the maximum breakage was 1.06 percent. The maximum fuel consumption is 2.347214 L/hr. The machine can significantly reduce drudgery and save time, energy, and cost of operation. As a suggestion, if engine changed to tractor attached will increase the requisition of technologies.

Sustainable management of potato tuber moth in storages using entomopathogenic fungi and an ectoparasitic mite.

The potato tuber moth (PTM), Phthorimaea operculella, is an economically important pest of potato crops worldwide. So far, the application of chemical pesticides is the major measure to manage PTM, but it induces serious deleterious impacts on the environment and human health. Here, we screened the entomopathogenic fungi that are lethal to PTM, and tested their sublethal impacts on PTM development, mortality, and reproduction as well as that of ectoparasitic mite Pyemotes zhonghuajia, a natural enemy of PTM. Among 13 tested entomopathogenic fungal strains in three genera, Beauveria Vuillemin, Cordyceps Fries, and Talaromyces Benjamin, Cordyceps fumosorosea (strain KY1136) and Beauveria bassiana (strain KY1115) caused a significantly higher mortality in PTM eggs, larvae, and pupae. Median lethal concentration (LC50) of both strains prolonged PTM immature development, shortened adult longevity, and reduced fecundity and life table parameters in terms of intrinsic rate of increase (rm), net reproductive rate (R0), and finite rate of increase (λ). The LC50 value of KY1136 (1.9 × 106 spores/mL) was lower than that of KY1115 (9.0 × 106 spores/mL), indicating the greater potential for biological control of PTM by KY1136. Both strains had no significant impact on P. zhonghuajia survival and reproduction. Increasing P. zhonghuajia density reduced PTM feeding and pupation rate, while the combined application of P. zhonghuajia and entomopathogenic fungi had no additional effect in inhabiting PTM feeding and pupation. Entomopathogenic fungal strains Cordyceps fumosorosea KY1136 and Beauveria bassiana KY1115 are the potential biological control agents of PTM, but do not impose a negative impact on the natural enemy. Our study provides insights into the integrated pest management of PTM by combining the entomopathogenic fungi and an ectoparasitic mite. © 2024 Society of Chemical Industry.

Delamination and thrust force analysis in GLARE: Influence of tool geometry and prediction with machine learning models

The multi-layered (fiber/metal) structure of glass fibre aluminium reinforced epoxy (GLARE) makes it difficult to obtain acceptable damage-free holes that meet aerospace standards. This paper investigated the effects of tool geometry and drilling parameters on reducing delamination damage and uncut fibers at the hole exit surface in drilling GLARE. The hole surfaces were examined by scanning electron microscope (SEM) at various magnifications. In addition, deep neural network (DNN) and long-short-term memory (LSTM) machine learning models were used to predict delamination (Fda), uncut fiber (UCF), and thrust forces using experimental data. No positive contribution of the special geometry tool was observed, while the standard geometry tool was found to be ideal for drilling conditions. Analysis of variance (ANOVA) revealed that feed rate contributed 57.83% to delamination damage, while tool geometry contributed 74.31% and 92.33% for uncut fiber and thrust force, respectively. SEM analysis revealed high deformation zones in the aluminum layers and fiber fracture and separation in the glass fibre reinforced polymer (GFRP) layers. DNN and LSTM models were found to provide accurate predictions with R2 values greater than 95% and 98%, respectively.

Enhancing Friction Stir Welding Performance: Finite Element Simulation Study using Filler Material

Friction Stir Welding (FSW) is a groundbreaking method that revolutionizes welding by utilizing friction-induced heat to join metals without melting them. In this study, we conducted a comprehensive investigation into the FSW process using the numerical software Simufact Forming, focusing on the critical aspect of introducing filler material during the welding operation. Our work involved meticulous simulations to analyze the impact of filler material on the quality and integrity of the weld joint. Through detailed modelling and parameter optimization, we successfully demonstrated the significance of the refill stage in achieving superior welding outcomes. Our main results reveal a substantial enhancement in the weld joint's mechanical and metallurgical properties when filler material is strategically introduced. The simulations provided valuable insights into the optimal conditions for the refill stage, including tool movement, material feeding rates, and key process parameters. These findings contribute to the ongoing efforts in refining FSW techniques, facilitating the development of high-performance welded joints.

Exploring the Tribological Performance of Mist Lubrication Technique on Machinability Characteristics During Turning S235JR Steel

The main challenges in turning are the quality of the machined part and the cost of tooling. Therefore, optimum machining parameters suitable for turning operations should be selected to achieve the desired quality of the finished product with reduced machining time and cost. The aim of this study is to determine the optimum machining conditions for S235JR low carbon steel without heat treatment, which could include finding the right combination of cutting speed, feed rate, depth of cut and tool material to achieve efficient material removal and desired surface finish. The experimental study, designed with the full factorial method, was carried out with 2 factors of cutting speed and feed rate with selected 2 levels under dry and MQL cutting environment conditions. Results of this study showed that mist lubricating technique overcome the machinability challenges of S235JR steel in terms of low surface quality and high cutting temperature and cutting force.

Effects of drilling parameters on drill bit wear of ASTM A36 steel

Drilling is a crucial process in metal manufacturing, with drill bits being key tools for creating holes in workpieces. During drilling, wear of the drill bits occurs inevitably. Several factors affect the wear of drill bits, such as materials, workpieces, and drilling parameters. The impact of these parameters on wear is investigated to understand the effects of drilling parameters on drill bit wear. This study used a diameter of 6 mm of uncoated high-speed steel drill bits to create the hole with 30 mm depth on ASTM A36 steel. The drilling was performed utilizing the DMG Mori DMU-50 5-axis drilling machine at three different levels of spindle speed (800, 1100, and 1400 rev/min) and feed rate (120, 135, and 150 mm/min). The sensor force dynamometer measured the thrust force and the cutting torque during drilling. However, many types of wear occur on drill bits during drilling. This research investigates only flank wear on the cutting edge of drill bits. The flank wear on the drill bits was measured with the overlap image technique using an Olympus SZ61 stereo microscope with a C-P3 OPTIKA digital camera. The results showed that adjusting drill parameters to increase the feed per revolution may result in a higher drill bit flank wear rate. Additionally, to quantify the wear of the drill bit based on the number of holes drilled, both the feed per revolution and the cutting distance per hole must be considered.

Cutting Parameter Optimization of Single Point Cutting Tool of CNC Lathe Machine Using Machine Learning Algorithm

In this study, two machine learning models, Random Forest Regressor (RFR) and Decision Tree Regressor (DTR), were applied to predict surface roughness (SR) in machining processes (turning) based on key input parameters: spindle speed (SS), feed rate (FR), and depth of cut (DOC). The performance of both models was evaluated using R² (R-squared), Mean Squared Error (MSE), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE). The Decision Tree Regressor achieved near-perfect accuracy with an R² score of 0.9999 and minimal error metrics. The Random Forest Regressor also performed exceptionally well, with an R² of 0.9988 and similarly low error values. Visual analyses, including residual and radar plots, confirmed the high accuracy of both models, with the Decision Tree Regressor slightly outperforming the Random Forest model. However, the Random Forest Regressor's ensemble structure provides better generalization and robustness, making it a more reliable model for larger or more complex datasets. This study concludes that both models are highly effective for predicting surface roughness, but the choice between them should depend on the specific trade-offs between accuracy and generalization needed in a given application.

ANALYSIS OF FRICTION STIR WELDING JOINTS ON HIGH DENSITY POLYETHYLENE (HDPE) DUE TO CHANGE IN MATERIAL TEMPERATURE AND SPINDLE ROTATION

Friction stir welding (FSW) can be a solution in solving the problem of joining thermoplastic polymers which are difficult to do with fusion welding. Selection of the proper FSW connection parameters can produce optimal connection quality in HDPE material joints. In friction stir welding, the heat of welding is used to raise the temperature of the material from its initial state to the solid state temperature. If the material temperature (T0) is increased above room temperature (TRoom), while the FSW welding parameter is constant, then at a certain increase in T0 it will produce excess welding heat which results in excessive softening or even melting of the material being welded. Therefore, the material temperature setting (T0) becomes an important parameter FSW The process of connecting the HDPE plates with friction stir welding was carried out by varying the material temperature (T0 ) of TRoom, 50 0C, 75 0C and 100 0C. While the spindle rotation varies 2000 rpm and 2500 rpm. Other parameters controlled include the type of square butt joint, 5 mm HDPE plate thickness, 20 mm/min feed rate, 0.1 mm plunge depth, 20 mm tool shoulder diameter, 4.5 mm pin length and 6 mm pin diameter. The result is that the higher the spindle rotation and the material temperature during the welding process causes the FSW peak welding temperature to increase. The highest peak weld temperature was obtained at variations in material temperature (T0) 100 °C with a spindle rotation of 2500 rpm, which is 123.2 °C or 94% of the melting temperature of HDPE. The hardness of the weld nugged area is still lower than the hardness of the base material. The highest average tensile strength of the research variations was achieved at a spindle rotation speed of 2500 rpm and a material temperature of 75 °C of 16.8 MPa, higher than the average tensile strength of the base material which is 15.1 MPa.

A Comparative Assessment of Hole Integrity with Twist Drill Geometry in Drilling AFRP/AL7075-T6 Stack Material

Drilling Aramid Fiber Reinforced Plastic (AFRP) with aluminium (AL7075-T6) is challenging. It is crucial to maintain the dimensional accuracy and minimize burr formation. In this study, two carbide drill bit were tested across 13 runs with varying combinations of feed rates (0.05, 0.08, 0.10 mm/rev) and spindle speeds (2000, 4000, 6000 rev/min), using a central composite design (CCD) methodology within the Design of Experiment (DOE) framework. The drill geometries included angles such as the helix angle, primary clearance angle, chisel edge angle, and point angle. For the tapered web drill bit, angles were set at 10º, 6º, 45º, and 130º, while for the burnishing drill bit, they were 20º, 8º, 30º, and 135º, respectively. The primary focus of the experiment was to assess hole quality, specifically evaluating hole diameter error and burr height formation. Among the 13 runs conducted, the tapered web drill bit exhibited superior performance in terms of hole diameter error, showing a deviation of-0.5 µm in Run 8, compared to a deviation of 1.2 µm for the burnishing drill bit in Run 12. Additionally, the tapered web drill bit demonstrated a lower burr height of 63.97 µm in Run 12, while the burnishing drill bit resulted in a burr height of 95.44 µm in Run 4. These findings enhance aircraft production by promoting better hole quality with optimal drill bits, leading to material savings, lower rejection rates and cost reduction, thus boosting reliability and productivity.