This study investigates the effects of tool geometry and cutting parameters on cutting forces in milling Al 7075 alloy, which is frequently preferred in the aerospace and automotive industries due to its high strength-to-weight ratio. Three-flute carbide end mills were specially manufactured with varying combinations of clearance angle (8°, 10°, 12°) and rake angle (14°, 18°, 22°). The experimental process used a Taguchi L9 orthogonal array with clearance angle, rake angle, and cutting speed (70, 85, 100 m/min) as control factors. Variance analysis (ANOVA) showed that cutting speed had the largest contribution ratio (40%) to cutting forces, with results serving as exploratory trend indicators. Signal-to-Noise (S/N) analysis identified 8° clearance angle, 18° rake angle, and 100 m/min cutting speed as the optimum combination for minimum cutting force. The lowest resultant cutting force measured was 469.72 N. The findings indicate that combining a small rake angle with a high cutting speed reduces cutting resistance and improves machining efficiency.

In industrial fields such as automotive and machinery manufacturing, the surface quality of polymer-based materials after machining is of great importance for functional performance, assembly accuracy, and service life. In this study, the surface roughness behavior of polyester-based samples containing different proportions of MEKP hardener after milling was experimentally investigated. In the experiments, two different polyester samples prepared with 1% and 2% MEKP addition by weight were machined on a CNC milling machine at different speeds, feed rates, and depths of cut. The surface quality after milling was evaluated using the mean surface roughness (Ra) parameter. The results obtained showed that the MEKP ratio and cutting parameters have a significant effect on surface roughness. Overall, it was determined that samples containing 1% MEKP exhibited lower or similar Ra values compared to samples containing 2% MEKP. This was attributed to the fact that increasing the MEKP ratio increases cross-linking density, making the material more brittle and negatively affecting machinability. Increasing the spindle speed had a surface roughness-reducing effect under all cutting conditions, and smoother surfaces were obtained, especially at medium and high-speed levels, thanks to more stable cutting conditions. In contrast, increasing the feed rate and depth of cut significantly increased the surface roughness. Increased cutting forces at high feed rates and large depths of cut led to increased surface tearing and micro-fractures, especially in the harder and more brittle samples containing 2% MEKP. However, it was observed that these negative effects were partially suppressed at high spindle speeds. Overall, the study results show that polyester-based materials with a low MEKP ratio offer better machinability and lower surface roughness in milling operations. Furthermore, it was concluded that the surface quality of polyester-based parts used in industrial applications such as automotive and machine manufacturing can be improved by selecting appropriate cutting parameters.

The crash box becomes a crucial component of the vehicle structure, special designed for energy-absorbing during collisions. This study aims to evaluate the performance of honeycomb structures in crash boxes and to investigate the deformation characteristics, energy absorption, and reaction force during crash tests. In this work, a novel crash box based on the hexagonal honeycomb structure with variations in the addition of circles at each hexagonal corner is proposed. The research configurations simulate a crushing test on the traditional honeycomb structure and variations CH 1, CH 2, CH 3 and CH 4. The honeycomb model was analyszed using different impactor velocity of 3 m/s and 4 m/s, with a mass of 500 kg. The result shows that increasing the size of the circle structures at each hexagonal honeycomb corner can increase crash energy absorption (EA). The CH 3 and CH 4 crash box structures offer the most increases in EA for each crash velocity than the traditional honeycomb. Higher impact velocities activate more stable progressive folding mechanisms in the honeycomb, thereby enhancing deformation efficiency during impact. The CH4 configuration exhibits higher SEA and MCF while maintaining a stable PCF, reflecting enhanced crashworthiness performance. This improvement is associated with progressive local buckling, which enables controlled and stable energy dissipation during impact. At a velocity of 3 m/s, the deformation pattern is consistent with previously reported studies, where the initial fold or fracture initiates in the middle of the honeycomb structure.

This study evaluates the effects of single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT) as diesel fuel additives on engine performance, combustion characteristics, and emissions under varying exhaust gas recirculation (EGR) rates (0%, 10%, and 20%) at a constant engine speed of 1800 rpm. The main purpose of the study is to determine the optimal carbon nanotube (CNT) type and concentration that enhance combustion efficiency while reducing exhaust emissions under different EGR conditions. SWCNT and MWCNT were blended with diesel at 25 ppm and 50 ppm concentrations to analyze their catalytic performance across different engine loads. All experiments were performed on a single-cylinder, four-stroke, air-cooled, direct-injection diesel engine (ANTOR 3LD510) with a displacement of 510 cm & sup3; and a compression ratio of 17.5:1, operating steadily at 1800 rpm. The results showed that MWCNT at 25 ppm achieved the highest cylinder pressure of 71.14 bar at 100% load with 0% EGR, compared to 73.55 bar for diesel. Cumulative heat release (CHR) increased significantly with MWCNT at 25 ppm, delivering a maximum of 41.48 MJ at 100% load under 20% EGR, compared to 39.97 MJ for diesel. Similarly, MWCNT at 25 ppm achieved the highest heat release rate (HRR) of 90 J/degrees CA, representing a marked improvement over diesel. In terms of engine performance, MWCNT at 25 ppm reduced brake specific fuel consumption (BSFC) to 252.81 g/kWh at 100% load under 0% EGR, compared to 279.85 g/kWh for diesel. Thermal efficiency improved to 37.38% at 100% load with 20% EGR for MWCNT at 25 ppm, compared to 34.42% for diesel. These results underscore the superior energy conversion efficiency achieved with MWCNT additives. Emission analysis revealed that MWCNT at 25 ppm reduced CO emissions to 0.03% and HC emissions to 11 ppm at 50% load under 10% EGR, compared to 0.034% CO and 18 ppm HC for diesel. Soot emissions were reduced to 0.02 mg/m & sup3; under 20% EGR at 100% load, compared to 0.21 mg/m & sup3; for diesel. However, NOx emissions increased to 1104 ppm under 0% EGR at 100% load for MWCNT at 25 ppm, compared to 1274 ppm for diesel, with reductions observed as EGR rates increased. This study concludes that MWCNT at 25 ppm is the most effective additive for enhancing engine performance and reducing emissions. These findings highlight its potential for optimizing combustion efficiency and meeting stringent emission regulations in diesel engines.

In this study, machine learning-based models were employed to estimate brake-specific fuel consumption (BSFC) using the data derived from 300 experimental engine tests conducted under varying loads, EGR ratios, and fuel combinations. Eleven alternative algorithms, including AdaBoost, Gradient Boosting, Random Forest, SVM, and Neural Network, were evaluated using datasets derived from real engine data. Statistical tools such as the R² coefficient and Mean Square Error (MSE) were utilized to assess the performance of the models. The best results were derived using Gradient Boosting (R² = 0.9998), AdaBoost (R² = 0.9998), and Random Forest (R² = 0.9997). In the prediction process of the Gradient Boosting model, the minimum absolute error was found to be 0.0000000, and the maximum absolute error was found to be 0.000002. The model's prediction accuracy ranges from 98.30% to 99.39%. This degree of accuracy demonstrates that fuel consumption can be predicted from engine data alone, without installing fuel-measurement equipment. The model's forecasting performance has been examined by analyzing the most and least successful examples. The results simplify fuel-consumption measurement procedures, provide the infrastructure for AI-supported test systems, and reduce time and labor. In this respect, the study significantly advances the digitization of engine testing in both academia and industry.

This study investigates the effects of process parameters on the mechanical properties in the friction stir welding of 5 mm thick Polyamide 6 plates in a butt-joint configuration using tools with two different pin geometries. In addition to the primary process parameters, rotational speed and transverse speed, the impact of various tool path patterns on weldability have also been examined. The experimental design was created based on the Taguchi L9 orthogonal array, regression and variance analyses were conducted to examine the effects of process parameters on mechanical properties. Optimum process parameters were determined based on signal-to-noise ratio (SNR) evaluations. In terms of mechanical characteristics, tensile strength tests, Shore D hardness measurements, and optical microscopic imaging have been used as references. As a result, it has been observed that the cylindrical-pin tool produces joints with higher mechanical properties compared to the threaded cylindrical-pin tool in general. In terms of weld strength, a maximum joint efficiency of 41.5

Enset fiber, a naturally abundant and low-cost material, offers promising potential as a sustainable reinforcement in composite applications. This study presents a comparative evaluation of Enset fiber reinforced composite (EFRC) and glass fiber reinforced composite (GFRC) under identical fiber orientation, volume fraction, and loading conditions using ANSYS Composite Prepost (ACP) and ANSYS Workbench. The composites were analysed for their flexural, tensile, impact, and modal responses. Simulation results reveal that EFRC develops lower stress magnitudes to resist the applied loads, indicating better load-bearing efficiency. Specifically, EFRC develops a tensile stress of 4.7098 MPa, while GFRC develops 5.0518 MPa under the same loading conditions. In the flexural analysis, the stress in EFRC is 32.289 MPa, whereas GFRC shows a higher value of 43.893 MPa. Similarly, in the impact test, EFRC records a stress of 11,736 MPa, compared to 26,462 MPa for GFRC. Moreover, modal analysis shows that EFRC has lower natural frequencies in all vibration modes, reflecting favourable damping characteristics and reduced stiffness. These findings indicate that EFRC performs more efficiently by developing less internal stress under equivalent loading, which can be advantageous in structural applications requiring energy absorption and vibration control. Considering its mechanical performance, environmental benefits, and cost-effectiveness, Enset fiber presents a viable alternative to synthetic fibers like glass in the production of lightweight and sustainable composite materials. Further experimental studies focusing on durability, moisture resistance, and fiber-matrix interface optimization are recommended to support the broader implementation of Enset fiber composites in real-world engineering applications.

In this study, the effects of novel tool path profiles on the weld quality of friction stir welded butt joints in thermoplastic plates were investigated. PE1000 polyethylene plates were used in the joining processes. Joining was achieved using zigzag, square, and straight tool path profiles with varying spindle speeds and feed rates. After tensile testing, welds with the zigzag tool path profile exhibited the highest tensile strength, followed by the square profile, with the straight tool path resulting in the weakest joint. Additionally, the fractured faces of the samples were subjected to scanning electron microscope (SEM) imaging after the tensile test. SEM images exposed more ductile surfaces and fewer defects in samples welded with zigzag and square profiles, while samples welded with a straight tool path showed lower joint formation and a flawed seam structure. Accordingly, in the SEM images of the specimens where the weakest strength occurred, insufficient melting agglomerations were observed. The Taguchi method was used to design experiments and determine optimal values based on tensile strength responses. Consequently, the optimum process parameters were determined as a spindle speed of 1400 rpm, a feed rate of 10 mm/min, and a zigzag tool path profile. Analysis of variance based on the signal-to-noise ratio revealed that the most significant parameter affecting the welded joint was the tool path profile.

This study investigates the mechanical properties of hybrid lattice structures produced using stereolithography (SLA), a type of additive manufacturing (AM) technology. In the research, three different basic lattice geometries [Gyroid (A), Cross (B), and X-Cell (C)] were combined in both vertical and horizontal orientations to create hybrid structures. The specimens were produced using an acrylonitrile butadiene styrene (ABS)-like photopolymer resin and subjected to static compression tests. In the vertically oriented hybrid lattice structures, the homogeneous Gyroid (AAA) specimen exhibited the highest compressive strength (4.20 MPa), energy absorption capacity (2.53 MJ/m(3)), energy absorption efficiency (62.43%), and specific strength (8.17 Nm/kg). In the hybrid structures, it was observed that the top layer played a critical role in the overall strength of the structure, with ABC and ACB specimens containing Gyroid showing high initial stiffness and strength. In the horizontally oriented hybrid lattice structures, the homogeneous Gyroid (AAA) structure also demonstrated the highest energy absorption (approximately 3.65 MJ/m(3)) and specific strength (6.29 Nm/kg) performance. Among the hybrid configurations, BAC (Cross-Gyroid-X-Cell) and CAB (X-Cell-Gyroid-Cross) structures, where the Gyroid unit is positioned in the middle, stood out with energy absorption capacities of 3.09 and 3.02 MJ/m(3), respectively. These arrangements exhibited more controlled and gradual collapse behavior, ensuring a more stable and higher energy absorption performance. This study contributes to the literature on the mechanical behaviors of hybrid lattice structures produced using the SLA method. The findings show that the type and arrangement of lattice cells have a significant impact on the mechanical properties of the structures.

In this study, the effects of production parameters on the mechanical properties of parts produced using the FFF (Fused Filament Fabrication) technique were investigated, along with the application of epoxy filling. The effects of layer thickness, infill density infill pattern, and epoxy filling on the mechanical performance of the specimens were analyzed. Microscopic images were used to evaluate the distribution and structural integration of the epoxy within the specimens. Experimental results revealed that increasing layer thickness led to a decrease in tensile strength, with the highest strength recorded at 0.1 mm and a significant reduction at 0.3 mm. Higher infill density improved tensile strength but reduced elongation percentage. Epoxy filling provided significant mechanical enhancement, particularly at low infill densities, increasing tensile strength by 12% at 20% infill density and by 8% at 60% infill density. Among the infill patterns, hexagonal infill achieved the highest tensile strength (18.89 MPa), while linear infill exhibited the lowest (15.28 MPa). The homogeneous distribution of epoxy improved mechanical performance, while inhomogeneous dispersion limited mechanical enhancement. Additionally, epoxy-filled specimens exhibited lower elongation percentages than non-epoxy specimens due to their increased rigidity. Specimens with 0.1 mm layer thickness exhibited the highest elongation at break (4.58%), whereas at 0.3 mm layer thickness, elongation decreased by approximately 30% to 3.51%. The results demonstrate the potential of epoxy filler material to improve the tensile strength of 3D-printed composite structures, providing a new perspective that can contribute to the future applications of additive manufacturing.

This study focuses on investigating the tensile strength of specimens produced using the Fused Filament Fabrication (FFF) method with Acrylonitrile Butadiene Styrene (ABS) material. The objective of the research is to evaluate the effect of different production parameters on the mechanical properties (tensile strength) of the specimens. Three different infill densities (20, 50, and 80

Producing vertical edged parts in sheet metal forming methods can cause tears on the sheet. The incremental forming method can allow sheet forming without tears. Forming can be done multi-stage to prevent this tear. Incremental forming method can be used in prototype production. The most important advantages of incremental forming method are that it is fast and inexpensive. In this study, we applied multi-stage forming to the two-point incremental forming-rolling blank holder method. Thus, we have developed a new way: the multi-stage, two-point incremental forming-rolling blank holder method. Parts with vertical edges are produced, and the wall thickness distribution is examined. The work material is a DC04 sheet with a thickness of 0.98 mm. The workpiece is axially symmetrical with a wall angle of 90°. The effect of four different parameters were researched: increment, feed rate, clamping pressure, and angle increment. Three different levels were determined for each parameter. The wall thickness distribution of the parts obtained from the experiments was measured.

In machining processes, the heat generated in the cutting zone varies depending on cutting parameters such as depth of cut, cutting speed and feed rate. On the other hand, in most existing machine tools, the flow rate of the coolant sent to the cutting zone is constant, and there is no additional cooling system in the tank. Therefore, the temperature of the coolant circulating in the closed circuit in the system is constantly increasing, which negatively affects cutting performance. This study aims to investigate the effect of coolant temperature on tool wear in the machining process and to control the coolant temperature. For this purpose, a comprehensive coolant temperature control system was developed and integrated into the CNC machine tool. Thanks to this system, it was possible to automatically control the temperature of the cutting fluid (coolant) and maintain it within a constant temperature range throughout the cutting process. Thus, experiments were conducted at different temperatures with different cutting parameters and coolant emulsion ratios using the developed system. Since the cutting parameters interact with each other, the Taguchi method was used to observe the effect of each parameter and to determine the optimum cutting parameters. As a result, it was observed that tool wear was reduced, tool life was extended and unnecessary coolant use was prevented, especially at low temperatures. In addition, the amount of coolant used is expected to reduce negative environmental impacts.

The usage of 3D printers in the production of parts is becoming widespread. Parts used in many different fields are produced with these printers. One of these fields is the aviation industry. It is desirable that the drones be as light as possible. 3D printers can respond to this demand. In this study, surface roughness optimization of the drone propeller produced on a 3D printer was performed. Layer height, infill rate, and printing speed are set as parameters. Compared to other parameters, it was seen that layer height was more effective at 90

In some manufacturing sectors, the effect of energy costs has a significant impact on unit product costs. In all manufacturing applications, unit consumption costs have become a point of attention. Part production time and, accordingly, energy consumption are related to many direct and indirect parameters in product costs. This effect is associated with the performance of CNC programs in the production of hollow parts, whose manufacturing practices have increased recently. In this study, the efficiency achieved by a manufacturing optimization was evaluated by referring to the through-hole drilling process of hollow parts on the CNC milling machine. An energy-efficient manufacturing process has been planned with a macro program developed in this context. Effective energy efficiency has been achieved in the system due to the shortening of the manufacturing process, especially with time management. At the end of the study, 40

Aluminum bronze alloys produced by various methods are preferred materials in many fields of the industry due to their high wear resistance and good sliding properties. This study investigated the tribological properties of aluminum bronze alloys produced by forging from Cu, Al, Fe, and Mg elements. Dry sliding wear tests were carried out on a pin-on-disc wear device. Three tribological properties, wear, friction coefficient, and temperature of aluminum bronze alloys were investigated. Experimental studies were carried out for different loads, sliding speeds, and sliding ways. The factorial experiment design method was applied in the MINITprogram. A SEM visualized the samples microstructures to examine the material wear characteristics. As a result of the study, it was deter-mined that the applied load, sliding speed, and sliding way were effective parameters on the amount of wear and friction coefficient. The maximum amount of wear was 0.352 mg at 100 N load, 3 m/s sliding speed, and 3000 m sliding way conditions. The maximum temperature between materials under these conditions is 299 oC. The minimum amount of wear was obtained when 25 N load, 1 m/s sliding speed, and 1000 m sliding way were applied.