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Öğe Assessment of the machinability and energy consumption characteristics of Cu-6Gr hybrid composites under sustainable operating(Springer Heidelberg, 2024) Usca, uesame Ali; Sap, Serhat; Uzun, Mahir; Degirmenci, UenalHybrid composites are at the forefront of technological developments due to their high thermal conductivity and thermal stability requirements. Hybrid composites are complex to machining due to the hard reinforcement particles contained in them and may cause structural defects. For this reason, although they are at the forefront, they are not preferred much in the manufacturing industry. This study was carried out to increase the machining efficiency of hybrid composites and, at the same time, to encourage the use of these composites in industry by reducing the environmental impact. In this study, the effects of different cooling/lubrication conditions on the surface roughness, tool wear, cutting temperature, and energy consumption of Cu-6Gr/SiC-WC hybrid composites by CNC milling were investigated. For this purpose, six material types (1-2-3-4-5-6), three cutting speeds (150-200-250 m/min), three feed rates (0.15-0.20-0.25 mm/rev), and three cooling/lubrication environment (dry-MQL-cryo-LN2) was selected. It was determined that the best option in terms of surface quality is the MQL environment. Cryo-LN2 environment reduces tool wear, cutting temperature, and energy consumption by 67%, 31%, and 14%, respectively, compared to the dry environment. Additionally, the wear mechanisms occurring on the cutting tool were examined by SEM/EDS analysis. In general, the cryo-LN2 strategy can be used as the best option for sustainable milling of hybrid composites. The results obtained are promising for using Cu-6Gr composites in the manufacturing industry, and these results are seen as innovations for the machinability results of hybrid composites.Öğe Determination of machinability metrics of AISI 5140 steel for gear manufacturing using different cooling/lubrication conditions(Elsevier, 2022) Usca, Usame Ali; Uzun, Mahir; Sap, Serhat; Giasin, Khaled; Pimenov, Danil Yurievich; Prakash, ChanderAISI 5140 steel is mostly used in gear manufacturing for variety of industries. Those gears can be manufactured via casting, powder metallurgy or forging techniques. Nevertheless, machining (via turning and milling processes) remains the most common manufacturing method to fabricate them. Milling of gears made from 5140 steel can be challenging due to the excessive energy consumption, rapid tool wear and poor surface finish. Therefore, traditional and environmentally friendly coolants are usually applied during machining to improve the surface finish and prolong tool life. The current study aims to investigate machinability performance of 5140 steel under different cooling/lubrication conditions. Several machinability metrics were investigated and analyzed (surface roughness, cutting temperature, tool wear, chip morphology, and energy consumption). Milling tests were performed under different cutting speeds (75 and 100 m/min), different feed rates (0.15 and 0.2 mm/rev) and dry, minimum quantity lubrication (MQL), and cryogenic liquid cooling/lubrication conditions (dry, MQL and cryo-LN2). The results showed that using Cryo-LN2 cooling/lubrication tended to improve all the investigated machinability metrics compared to dry condition. The surface roughness was reduced by approximately 54%, while the cutting temperature was reduced by 87%. Similarity, the cutting tool flank wear was reduced by 20% thus energy consumption was minimized by 15%. The current study shows the importance of cryogenic machining in industry for difficult to cut materials. (C) 2022 The Authors. Published by Elsevier B.V.Öğe Development of the hardness, three-point bending, and wear behavior of self-lubricating Cu-5Gr/Al2O3-Cr3C2 hybrid composites(Sage Publications Ltd, 2023) Sap, Serhat; Usca, Usame Ali; Uzun, Mahir; Giasin, Khaled; Pimenov, Danil YuThis research aims to assess the mechanical characteristics of high-performance copper composites made utilizing powder metallurgy. The composites were produced by adding reinforcement elements (Al2O3-Cr3C2) at different rates (3-6-9 wt.%) into copper-graphite (Cu-5Gr) via hot pressing technique. The microstructure, hardness, three-point bending and wear performance were analysed. The results determined that hybrid reinforced composites exhibited higher density, hardness and bending strength compared to Cu-Gr composites. The highest hardness of 73.02 HB was found in the CG-4 (copper graphit-4) sample. The maximum bending stress of 151.06 MPa occurred in sample CG-2. In addition, it was observed that the wear resistance increased significantly with the addition of the hybrid reinforcements. The lowest specific wear rate of 7.961 x 10(-7) mm(3)/N.m occurred in sample CG-6. As a result, 15.92%, 58.16% and 83.21% improvements were achieved in hardness, bending strength and wear performance, respectively. The current work indicates that certain mechanical properties of copper can be improved via the powder metallurgy process and the addition of reinforcements which could expand the applications and use of this metal in different industries.Öğe Estimation, optimization and analysis based investigation of the energy consumption in machinability of ceramic-based metal matrix composite materials(Elsevier, 2022) Usca, Usame Ali; Sap, Serhat; Uzun, Mahir; Kuntoglu, Mustafa; Salur, Emin; Karabiber, Abdulkerim; Pimenov, Danil YuThe current study aims to determine the influence of machining and production parameters during the milling of Cu/B-CrC composites. The relationship between energy consumption and cutting speed, feed rate and reinforcement ratio were investigated. For this purpose, 2d and 3d graphs for comparison of the effects of input parameters were demonstrated and analyzed. The predictability of the energy consumption during milling was measured by a fuzzy inference system (FIS). According to the graphical and optimization results, the optimum conditions to obtain the minimum energy consumption were 5% reinforcement ratio, 125 m/min cutting speed and 0.2 mm/rev feed rate. A reinforcement ratio of 52.71% was the most effective factor on energy demand followed by the feed rate (24.26%) and cutting speed (12.85%). According to the obtained results, there was a minor margin of error between the actual and predicted findings ranging from 1.6 to 2.4%. Considering the energy consumption is one of the key factors among machinability criteria, the study proposes a comprehensive approach for industrial and academic works. (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Öğe Evaluation of Machinability of Cu Matrix Composite Materials by Computer Numerical Control Milling under Cryogenic LN2 and Minimum Quantity Lubrication(Springer, 2023) Usca, Usame Ali; Sap, Serhat; Uzun, MahirThis study focuses on the machinability properties of hybrid reinforced (Co-Mo) copper matrix composite materials. For this purpose, surface roughness (R-a), flank wear (V-b), and cutting temperature (T-c) analyses of hybrid composite materials were performed using CNC milling with dry, air, MQL (minimum amount of lubrication) and cryogenic LN2 cooling/lubrication supports. Two different cutting speeds (200-300 m/min) and two different feed rates (0.2-0.3 mm/rev) were used as cutting parameters. Taguchi L-16 orthogonal array was chosen in the experimental design. In addition, chip morphologies of composites processed with different cooling/lubricating supports were examined. As a result, it was seen that the most effective factor on R-a, V-b and T-c levels was cooling/lubrication. A(4)B(1)C(3)D(2) (reinforcement rate-level 4, cooling conditions-level 1, cutting speed-level: 3, feed rate-level: 2) equations for surface roughness, A(3)B(1)C(4)D(2) (reinforcement rate-level 3, cooling conditions-level 1, cutting speed-level: 4, feed rate-level: 2) for flank wear and A(3)B(1)C(4)D(2) (reinforcement rate-level 3, cooling conditions-level 1, cutting speed-level: 4, feed rate-level: 2) for cutting temperature were obtained. Compared to dry machining, approximately 88% improvement in surface roughness, approximately 72% improvement in flank wear and approximately 56% improvement in cutting speed was noted. It was determined that the chips obtained during the CNC milling experiments were of the desired type and size. The most suitable chip was cryo-LN2 type.Öğe Evaluation of Mechanical and Tribological Aspect of Self-Lubricating Cu-6Gr Composites Reinforced with SiC-WC Hybrid Particles(Mdpi, 2022) Usca, Usame Ali; Sap, Serhat; Uzun, Mahir; Giasin, Khaled; Pimenov, Danil YurievichBecause of their high thermal conductivity, good corrosion resistance, and great mechanical qualities, copper matrix composites are appealing materials utilized in a variety of industries. This study investigates the mechanical properties of copper-graphite (Cu-Gr) matrix composites reinforced with silicon carbide (SiC) and tungsten carbide (WC) particles by hot pressing using powder metallurgy method. The goal is to investigate the influence of the reinforcement ratio on the mechanical characteristics of copper composite materials generated (density, hardness, flexural strength, and wear resistance). SEM, EDS, and X-RD analysis were used to perform metallographic examinations. The highest relative density with a value of 98.558% was determined in the C3 sample. The findings revealed that when the reinforcement ratio was raised, the hardness rose. The highest hardness value was observed in the C6 sample with an increase of 12.52%. Sample C4 (with the lowest SiC and WC particles ratio) had the highest bending stress (233.18 MPa). Bending stress increased by 35.56% compared to the C1 sample. The lowest specific wear rates were found in the C4 sample, with a decrease of 82.57% compared to the C1 sample. The lowest wear rate (6.853 x 10(-7) mm(3)/Nm) also occurred in the C4 sample. The microstructural analysis showed that the hybrid reinforcement particles exhibited a homogeneous distribution in the copper matrix. X-RD analysis showed that there was no intermediate reaction between the parent matrix and the hybrid reinforcements. A good interfacial bond was observed between the matrix structure and the hybrid reinforcements. The motivation of this research was to utilise the advantages of the unique features of SiC-WC hybrid particles to improve the performance of newly developed Cu-6Gr composites for wear-resistance applications.Öğe Investigation of machinability of Ti-B-SiCp reinforced Cu hybrid composites in dry turning(Elsevier, 2022) Sap, Serhat; Uzun, Mahir; Usca, Usame Ali; Pimenov, Danil Yu; Giasin, Khaled; Wojciechowski, SzymonMMCs (metal matrix composites) are widely used in many industrial applications thanks to their high specific strength. Nevertheless, this also poses a great challenge to their machinability due to rapid tool wear and poor surface finish caused by the added reinforcement particles. Improving the machinability of MMCs is of great importance as it will increase their performance and areas of applications. In this study, the machinability of Cu composites reinforced with Ti-B-SiC powder particles (0-2-4-6-8 wt.%) produced at different rates using powder metallurgy method was investigated. Cutting speed (V-c: 100-150 m/min) and feed rate (f(n): 0.2-0.4 mm/rev) were used as cutting parameters. The effects of these parameters on surface roughness, flank wear, and cutting temperature were investigated. As a result of the turning experiments, it was observed that the surface roughness decreased with increasing reinforcement ratio, and thus the best surface roughness (R-a = 0.22 mu m) was observed in the 8 wt.% reinforced sample. The cutting temperature and flank wear values increased as the reinforcement ratio increased. It was observed that cutting temperature at the chip-tool interface was the lowest (76 degrees C) in MMCs sample with 2 wt.% reinforcement. The lowest flank wear (0.93 mm) was also observed in the 2 wt.% reinforced sample. In addition, the chip morphologies of all samples produced at different ratios were investigated after the turning process. (C) 2022 The Authors. Published by Elsevier B.V.Öğe Investigation of microstructure and mechanical properties of Cu/Ti-B-SiCP hybrid composites(Elsevier Sci Ltd, 2021) Sap, Serhat; Turgut, Aydin; Uzun, MahirIn this study, Cu/Ti-B-SiCp hybrid composite materials were produced by powder metallurgy method using three different sintering temperatures (950, 1000, 1050 degrees C). The optimum sintering temperature of Cu main matrix composites reinforced with Ti-B-SiCp reinforcement materials at 2-4-6-8 wt.% were determined and their microstructure and mechanical properties were investigated. As a result of microstructure studies, it was determined that reinforcement elements have a homogeneous interface in the main matrix. The hardness of the produced composites was determined by the Brinell hardness method. The highest hardness value (77.74 HB) was determined in the sample with 6 wt% reinforcement ratio. In the tensile and three point bending tests, maximum strength values (112.96 MPa, 37.76 MPa) were found in samples with a reinforcement ratio of 4 wt%. It was determined that increasing reinforcement ratios and sintering temperature made a positive contribution to the hybrid composite materials produced.Öğe Investigation of the Effects of Cooling and Lubricating Strategies on Tribological Characteristics in Machining of Hybrid Composites(Mdpi, 2022) Sap, Serhat; Usca, Usame Ali; Uzun, Mahir; Kuntoglu, Mustafa; Salur, Emin; Pimenov, Danil YurievichEngineering materials are expected to contain physical and mechanical properties to meet the requirements and to improve the functionality according to their application area. In this direction, hybrid composites stand as an excellent option to fulfill these requests thanks to their production procedure. Despite the powder metallurgy method that allows for manufacturing products with high accuracy, machining operations are still required to obtain a final product. On the other hand, such materials are characterized with uncertainties in the structure and extremely hard reinforcement particles that aggravate the machinability. One of the prominent solutions for better machinability of composites is to use evolutionary cooling and lubricating strategies. This study focuses on the determination of tribological behavior of Cu-based, B-Ti-SiCP reinforced, about 5% wt. hybrid composites under milling of several environments, such as dry, minimum quantity lubrication (MQL)-assisted and cryogenic LN2-assisted. Comprehensive evaluation was carried out by considering tool wear, temperature, energy, surface roughness, surface texture and chips morphology as the machinability characteristics. The findings of this experimental research showed that cryogenic cooling improves the tribological conditions by reducing the cutting temperatures, flank wear tendency and required cutting energy. On the other hand, MQL based lubricating strategy provided the best tool wear index and surface characteristics, i.e., surface roughness and surface topography, which is related to spectacular ability in developing the friction conditions in the deformation zones. Therefore, this paper offers a novel milling strategy for Cu-based hybrid composites with the help of environmentally-friendly techniques.Öğe Investigation on microstructure, mechanical, and tribological performance of Cu base hybrid composite materials(Elsevier, 2021) Sap, Serhat; Uzun, Mahir; Usca, Usame Ali; Pimenov, Danil Yu; Giasin, Khaled; Wojciechowski, SzymonCopper matrix composites (CMC) are frequently used in the automotive, aerospace, construction, and electrical-electronics industries. Properties such as low density, improved fatigue strength, high hardness, and high specific strength are the factors that make copper matrix composites important. The development of these factors is important for the industrial use of copper matrix composites. SiCp doped metal matrix composites have better mechanical properties than pure alloys. It is also known that Ti, B powder particle additives improve the mechanical properties of the main matrix. In this study, Cu hybrid composites reinforced with Ti-B-SiCp powders, which were not produced before, were obtained and their microstructure, density, hardness, and wear behavior were investigated. Composite materials produced by powder metallurgy method were prepared at 2-8 wt. % mixing ratios. Then each material was sintered at temperatures of 950-100-1050 degrees C. Microstructural images showed homogenous distribution in the composite material. The highest relative density of 93% was obtained in the composite material with a 2% reinforcement rate at 1050 degrees C. It was found that the hardness increased with the increase of the reinforcement rate up to 6 wt.% and then decreased after that. It was observed that the specific wear rate increased with the increasing reinforcement ratio. In addition, the lowest friction coefficient and wear temperature occurred at a sintering temperature of 1050 degrees C. In this study, it was reported that the sinter temperature value of 1050 degrees C is the optimum temperature value in terms of the tribological and mechanical performance of the materials. (C) 2021 The Authors. Published by Elsevier B.V.Öğe Performance evaluation of AlTiN coated carbide tools during machining of ceramic reinforced Cu-based hybrid composites under cryogenic, pure-minimum quantity lubrication and dry regimes(Sage Publications Ltd, 2022) Sap, Serhat; Usca, Usame Ali; Uzun, Mahir; Kuntoglu, Mustafa; Salur, EminIn this study, the machining performance of 10 wt.% B-Ti-SiCp particles reinforced Cu-based hybrid composites were investigated under dry, minimum quantity lubrication (MQL) and cryogenic LN2 assisted environments during milling. In-depth analyses comprising of tool wear development, surface roughness, surface texture, cutting temperature, cutting energy, and chip morphologies were thoroughly performed. According to the experimental results, MQL environment was found to be most influential method to prevent build-up-edge formation. In addition, LN2 assisted cryogenic coolant medium is the most powerful method in all machining characteristics as providing better tribological properties. The paper proposes a novel approach for improved machinability performance of Cu-based hybrid composites with sustainable techniques.Öğe Tool wear, surface roughness, cutting temperature and chips morphology evaluation of Al/TiN coated carbide cutting tools in milling of Cu-B-CrC based ceramic matrix composites(Elsevier, 2022) Usca, Usame Ali; Uzun, Mahir; Sap, Serhat; Kuntoglu, Mustafa; Giasin, Khaled; Pimenov, Danil Yu; Wojciechowski, SzymonCeramics-based composites are a special class of materials carrying combined properties that belongs to alloys and metals according to market demands. This makes composites completely different and paves the way for new applications that requires the utmost properties. Machining of such composites is of great importance to finalize the fabrication process with improved part quality; however, the process implies several challenges due to the complexity of the cutting processes and random material structure. The current study aims to examine the machinability characteristics when milling novel material, Cu-B-CrC composites using Al/TiN coated carbide tools. Further, the influence of machining parameters along with the different weight ratios of the powders amounts used to fabricate the machined reinforced samples on output parameters namely surface roughness, tool wear, chip morphology and cutting temperatures was investigated. One of the key findings of the study is the dominant effect of reinforcement ratio (Cu, B, CrC) on machinability, which showed that 5% additive (2% B, 3% CrC) provides improved properties such as surface roughness, tool wear and cutting temperature. Cutting speed alterations play an important role in the machinability characteristics, i.e., increasing value increases flank wear and cutting temperatures and reduces surface roughness. Increasing feed rate in-creases the surface roughness meanwhile its effect shows changing behavior on the flank wear and cutting temperatures according to cutting speed and reinforcement ratio.(c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Öğe Tribological Aspects, Optimization and Analysis of Cu-B-CrC Composites Fabricated by Powder Metallurgy(Mdpi, 2021) Usca, usame Ali; Uzun, Mahir; Kuntoglu, Mustafa; Sap, Serhat; Giasin, Khaled; Pimenov, Danil YurievichTribological properties of engineering components are a key issue due to their effect on the operational performance factors such as wear, surface characteristics, service life and in situ behavior. Thus, for better component quality, process parameters have major importance, especially for metal matrix composites (MMCs), which are a special class of materials used in a wide range of engineering applications including but not limited to structural, automotive and aeronautics. This paper deals with the tribological behavior of Cu-B-CrC composites (Cu-main matrix, B-CrC-reinforcement by 0, 2.5, 5 and 7.5 wt.%). The tribological characteristics investigated in this study are the coefficient of friction, wear rate and weight loss. For this purpose, four levels of sliding distance (1000, 1500, 2000 and 2500 m) and four levels of applied load (10, 15, 20 and 25 N) were used. In addition, two levels of sliding velocity (1 and 1.5 m/s), two levels of sintering time (1 and 2 h) and two sintering temperatures (1000 and 1050 degrees C) were used. Taguchi's L-16 orthogonal array was used to statistically analyze the aforementioned input parameters and to determine their best levels which give the desired values for the analyzed tribological characteristics. The results were analyzed by statistical analysis, optimization and 3D surface plots. Accordingly, it was determined that the most effective factor for wear rate, weight loss and friction coefficients is the contribution rate. According to signal-to-noise ratios, optimum solutions can be sorted as: the highest levels of parameters except for applied load and reinforcement ratio (2500 m, 10 N, 1.5 m/s, 2 h, 1050 degrees C and 0 wt.%) for wear rate, certain levels of all parameters (1000 m, 10 N, 1.5 m/s, 2 h, 1050 degrees C and 2.5 wt.%) for weight loss and 1000 m, 15 N, 1 m/s, 1 h, 1000 degrees C and 0 wt.% for the coefficient of friction. The comprehensive analysis of findings has practical significance and provides valuable information for a composite material from the production phase to the actual working conditions.Öğe Tribological behaviors and mechanical properties of novel Al-5Cu hybrid composites under dry sliding conditions(Sage Publications Ltd, 2024) Sap, Serhat; Degirmenci, Unal; Usca, Usame Ali; Uzun, MahirThis study aims to develop aluminum composites, which are widely used in the automotive and aerospace industries. For this purpose, novel Al-5Cu/Al2O3-SiC hybrid composites were produced, and their mechanical and tribological performances were investigated. Hardness, density, and three-point bending analyses of hybrid composites were performed. In addition, wear and friction analyses were carried out under dry sliding conditions and applying different loads (5-10-15 N). In addition, the morphological properties of the produced hybrid composites were determined by microstructural analysis (SEM/EDS). High density, hardness, and strength values were obtained in hybrid composites produced using powder metallurgy and hot pressing methods. As a result of the wear test, it was determined that the hybrid reinforcements showed positive effects on the wear resistance. The lowest specific wear rate (SWR) value was 2.09 x 10-6 mm3/N.m. It was determined that the SWR values of the hybrid composites decreased with the increase of the applied load. In addition, plastic deformation and adhesion wear were observed as a result of SEM/EDS analyses taken from the worn surfaces.
