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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 Design and analysis of a pressure vessel according to EU 2014/29(Walter De Gruyter Gmbh, 2020) Uzun, Mahir; Bozkurt, SerkanIn this study, the production and analysis of a composite vessel were performed. The materials selected for the design of the composite materials were glass fiber/epoxy, carbon fiber/epoxy and Kevlar fiber/epoxy material. Anti-symmetric orientation angles of (30 degrees-30 degrees), (45 degrees-45 degrees), (60 degrees-60 degrees) and (75 degrees-75 degrees) were used for each material. In the design of the vessel, the total thickness of the wall is defined as 3 mm. The containers were modeled using the SOLIDWORKS package program with the wall thickness of 10 and 20 layers. The containers modeled are then analyzed to determine maximum deformation and maximum stress by using the ANSYS WORKBENCH 14.0 package program which analyzes according to the finite element method. While making solutions, a pressure of 1.65 MPa as the test pressure of the vessel was defined as hydrostatic from the inner surface of the vessel, and von-Mises stress and total deformations were determined. As a result of this study, it has been determined that a 60 degrees-60 degrees orientation angle is the most appropriate design angle considering both the deformation values and maximum stress. Maximum stress in the design of composite containers was far below the flow limit and remained within acceptable limits for shape changes.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 Effects of VCN coating of PEEK gears with the PVD method on wear performance(Springer, 2024) Cureoglu, Arif; Uzun, Mahir; Sap, EmineIn this study, the effects of coating gear wheels made of PEEK material, which is frequently used in the industry, with the PVD method on the tribological performance were investigated. Spur gears with 6 modules, 15 teeth, and 20 mm surface width consisting of PEEK samples were used as the base material. Gears modeled in Solidworks were manufactured on a CNC milling machine. The coating process was performed with VCN target material in three different thicknesses. After the coating process, hardness and wear tests were applied to the samples. An increase in the hardness values of the samples coated in different thicknesses was observed compared to the pure PEEK material. As the coating thickness increased, the amount of wear on the gear wheels increased and it was determined that the most resistant sample against wear was the gear wheel with a coating thickness of 367 nm. In experiments conducted in different liquids, it was observed that the most wear occurred in NaCl solution.Öğe Eriyik Yığma Modellemesi ile Üretimde Takviyesiz ve Takviyeli PLA Kullanımının Mekanik Özelliklere Etkisinin Araştırılması(2020) Uzun, Mahir; Erdoğdu, Yusuf ErenSon yıllarda eriyik yığma modellemesi (EYM) ilkeleriyle çalışan 3 boyutlu (3B) yazıcılarınkullanımı birçok alanda yaygınlaşmıştır. Bu teknoloji sayesinde başta prototipler olmak üzere karmaşıkşekilli parçalar dahi kısa sürede ve hassas şekilde üretilebildiğinden çoğu sektörde araştırma geliştirme(AR-GE) çalışmalarının olmazsa olmazı haline gelmiştir. EYM işlemiyle birlikte çevresel kaygıların daetkisiyle doğada çözünümü kolay olan (biyobozunur) polilaktik asit (PLA) filamentlerin kullanımıönemli hale gelmiştir. Bundan dolayı PLA filamentlere çeşitli takviyeler yapılarak bazı özellikleriningeliştirilmesi ve kullanımının yaygınlaştırılması önem arz etmektedir. Bu çalışmada da takviyesiz, %20bakır takviyeli ve %20 karbon-fiber takviyeli PLA kompozitler 3B yazıcı ile üretilmiştir. Üretilennumuneler çekme testine ve üç nokta eğilme testine tabi tutularak mekanik özellikleri kıyaslanmıştır.PLA malzemeye bakır ve karbon fiber takviyeler yapmanın çekme ve eğilme dayanımlarını düşürdüğügörülmüştür.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 Influence of tool path strategies on machining time, tool wear, and surface roughness during milling of AISI X210Cr12 steel(Springer London Ltd, 2022) Uzun, Mahir; Usca, Usame Ali; Kuntoglu, Mustafa; Gupta, Munish KumarIn this study, the effect of four different machining methods consisting of Trochoidal, Follow Part, Zig, and Zig-Zag which are common in CAM package programs and used often in the industry has been investigated. Firstly, the 3D model of samples is produced in the CAD program. Models are machined in CNC milling workbench. In order to examine the effect of tool path strategies on tool life, the amount of wear loss as a criterion and the SEM images of tool wear as a supporting criterion are taken into account. According to the results, the Zig-Zag tool path strategy is the tool path that causes the highest weight loss in the cutting tool, while the Trochoidal tool path strategy causes in the least weight loss in the cutting tool. In addition, the surface roughness of the samples taken from different regions of the model and the operation time of the different tool paths are determined. In this context, the operation time of the test sample is maximum in Zig team path strategy, while it is at least in Follow part team path strategy. By examining the surface roughness, the best surface roughness values are obtained with the strategy of Follow Part and Trochoidal tool path, while the worst values are obtained in the Zig tool path strategy. As a result of the examination, the optimum tool path strategy for cutting tool life was found to be Trochoidal tool path. This work differs from the counterparts as handling the AISI X210Cr12 steel which make the paper first in determining the effect of tool path strategies on machinability. Lastly, obtained findings are useful for the organization of this type of steel in manufacturing chain of industrial companies.Öğe Investigation of characteristics of Cu based, Co-CrC reinforced composites produced by powder metallurgy method(Elsevier, 2021) Uzun, Mahir; Cetin, Mehmet SinanThis study was carried out to assess the contribution of Co and CrC reinforcement particles to Cu main matrix powders by powder metallurgy (P/M) method as well as to mechanical properties, abrasion resistance and microstructure properties. For this purpose, the matrix material Cu powders, Co and CrC reinforcement particles, of which the weight percents are as follows: 5% (2% Co + 3% CrC), 10% (4% Co + 6% CrC) and 15% (6% Co + 9% CrC), were added. The samples were produced by cold pressing at room temperature and 450 MPa pressure, using the P/M method. Microstructure characterization of composite samples was performed by SEM-EDS and XRD analysis. Mechanical characterization of composite samples was carried out by analyzing the data of density determinations, hardness measurements, abrasion resistance tests and tensile tests. As a result of this study, it was observed that as the reinforcement ratio increased, the relative density of the samples decreased while the hardness of the samples increased. As a result of the findings obtained from the analysis of the tensile tests and other tests performed, it was clearly seen that the reinforcement particle ratio of wt. 10% was the optimum reinforcement ratio for this study. (c) 2021 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.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 Investigations on tool wear, surface roughness, cutting temperature, and chip formation in machining of Cu-B-CrC composites(Springer London Ltd, 2021) Usca, Usame Ali; Uzun, Mahir; Kuntoglu, Mustafa; Sap, Emine; Gupta, Munish KumarComposites have excellent material properties such as lightness, rigidity, and strength with reinforcement of specialized materials to serve an extended field in engineering. Meanwhile, some restrictions due to the production process lead to poor machinability characteristics and show reduced surface quality, excessive cutting temperature, and tool wear. The principal aim in this study is to research the machinability characteristics of Cu matrix reinforced by B and ceramic CrC powders during dry turning operation. In addition to reinforcement ratio, cutting speed, feed rate, and depth of cut were taken into consideration according to Taguchi L-8 orthogonal array in the experimental plan. Seemingly, reinforcement ratio is the governing factor over turning parameters on flank wear, surface roughness, and cutting temperatures. For the secondary effect, cutting speed and feed rate have contributing impact on cutting temperatures and surface roughness, respectively. Lastly, reinforcement ratio has significant impact on chip formation since deformation mechanism in the material is changed with cutting initiation. Accordingly, new additives reveal unique structure which is intriguing and need to be discovered for measuring the machinability behavior of metal matrix composites.Öğe Machining and optimization of reinforced copper composites using different cooling-lubrication conditions(Springer Heidelberg, 2022) Sap, Emine; Usca, Usame Ali; Uzun, MahirDuring the processing of metal matrix composite materials, some negative situations may occur due to the interaction between the tool and the workpiece. Wear and damage may occur on the side surfaces of the cutting tool used. In order to eliminate these adverse conditions, generally cooling liquids are used. In this study, the machinability properties of cryogenic LN2 and minimum quantity lubrication (MQL) techniques on Co-Ti added copper composites were investigated using CNC milling. Taguchi L-16 orthogonal array was chosen as the experimental design. The machining parameters testing, 2 distinct cutting speeds (200-300 m/min), 2 distinct feed rates (0.2-0.3 mm/rev), and a single cutting depth (0.25 mm) were used. Copper composites produced at different rates (0-5-10-15 wt. %); surface roughness, tool wear, cutting temperature and chip morphologies were investigated. Taguchi and analysis of variance (ANOVA) were used to assess the impacts of cutting parameters on surface roughness, flank wear, and cutting temperature. Cryo-LN2 was found to be the best cutting environment for surface roughness, flank wear and cutting temperature. Chips obtained with cryo-LN2 were found to be more efficient. [GRAPHICS] .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 PVD Yöntemi Kullanılarak Kaplanan PEEK Numunelerin Mekanik Özelliklerinin İncelenmesi(2023) Cüreoğlu, Arif; Şap, Emine; Uzun, MahirPolimer malzemeler endüstride özellikle farklı makine elemanları olarak yaygın bir şekilde kullanılmaktadırlar. Kullanıldıkları ortamlarda, metal malzemelere kıyasla aşınma dayanımları özellikle kimyasal ortamlar da söz konusu olduğunda oldukça düşük olmaktadır. Dolayısı ile polimer malzemeler, bu ortamlara daha dayanıklı elementler ile kaplanabilirlerse dayanımları çok daha yüksek olacaktır. Bu çalışmada, dayanımı arttırabilmek amacıyla literatürde rastlanılmayan PEEK (polieter eter keton)’un PVD yöntemlerinden biri olan manyetik alan sıçratma yöntemi ile kaplaması gerçekleştirilmiştir. Altlık malzeme olarak 30x30 mm² boyutlarında kare kesitli, 3 mm kalınlığında 3 adet saf PEEK numuneler kullanılmıştır. Numunelerin yüzeyi, kalın taneliden ince taneliye doğru sırası ile 400, 600 ve 1200 numara kum zımparası ile yüzey pürüzlülük değeri ortalama Ra=0.248 olana kadar parlatılmıştır. Daha sonra PEEK numuneler PVD (Fiziksel Buhar Biriktirme) kaplama yöntemlerinden olan manyetik alanda sıçratma yöntemi kullanılarak biri VN diğeri ise CrY(V)N ile kaplanmıştır. Kaplama işleminden sonra numunelere sertlik ve aşınma testi uygulanmıştır. Sonuç olarak, saf haldeki PEEK numuneye göre VN kaplanmış PEEK numunenin sertlik değerinin %34 arttığı, CrY(V)N kaplanmış PEEK numunede ise sertlik değerinin yaklaşık %40 arttığı görülmüştür. Aşınma deneyi ile ilgili olarak yükteki artış sonucunda, numunelerde aşınma kayıpları da artmıştır. En yüksek kütle kaybının CrY(V)N ve VN kaplı numunede olduğu görülmüştür.Öğe Sikloid, Episikloid, Evolvent, 45° Eğri Yüzeylerin Yapıştırılması Ve Mekanik Özelliklerinin Sonlu Elemanlar Yöntemi İle Araştırılması(2022) Uzun, Mahir; Akçadağ, BaharBu çalışmada, farklı yüzey geometrisine sahip sikloid, episikloid, evolvent ve 45 derece eğriler matematiksel formüller yardımıyla Solidworks programında modellenmiştir. Oluşturulan eğri yüzeyli uç uca yapıştırılan yapıştırma bağlantı modellerinin ANSYS analiz programında mesh işlemi yapılmıştır. Bu işlemden sonra bağlantı numunelerinin çekme ve eğme sonlu eleman analizleri yapılmıştır. Analizler esnasında yapıştırılan malzeme olarak St52 yapı çeliğinin malzeme özellikleri tanımlanmıştır. 45 derece eğri yüzeye sahip numunelerde, yapıştırıcı bağlantıların hasar yükü bulunmuş ve daha sonra bu hasar yükü referans alınarak diğer eğri yüzeye sahip numunelere de sırasıyla uygulanmıştır. Yapılan analizler sonucunda maksimum çekme ve maksimum eğme dayanımına sahip olan eğri yüzeyin, 45 derece eğri yüzey olduğu belirlenmiştir.
