Yazar "Erkan, Ömer" seçeneğine göre listele
Listeleniyor 1 - 9 / 9
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe CUTTING TOOL GEOMETRY IN THE DRILLING OF CFRP COMPOSITE PLATES AND TAGUCHI OPTIMISATION OF THE CUTTING PARAMETERS AFFECTING DELAMINATION(Yildiz Technical Univ, 2018) Sur, Gökhan; Erkan, ÖmerIt is possible to improve the hole quality by reducing the delamination which occurs in the drilling of carbon fibre reinforced plastic (CFRP) composite plates. For this study, carried out under dry machining conditions, the parameters included three different cutting speeds, three different feed rates and drill geometry involving three different point angles. The Taguchi L-9 orthogonal array experimental design was selected and the optimum cutting parameters and drill geometry for reducing the damage factor to a minimum were determined. The optimum test conditions were achieved using the parameter combination of 118 degrees point angle, 30 m/min cutting speed and 0.06 mm/rev feed rate (A1B1C1). In addition, variance analysis (ANOVA) was conducted to determine the effect rate of the parameters on the damage factor. The variable having the greatest effect on the damage factor was found to be the point angle (47.66%), followed by the cutting speed (24.44%) and feed rate (19.82%). The conditions for minimising delamination damage in the drilling of the CFRP plates were optimised successfully by using the Taguchi test design.Öğe The effect of full annular rub on the rotating machinery system considering different rub materials and shaft running speeds(2013) Saruhan, Hamit; Sarıdemir, Suat; Erkan, ÖmerIn this study, the effect of full annular rub on the rotating machinery system considering different rub materials and shaft running speeds was experimentally studied. Experiments were carried out for the rub materials - copper, bronze, brass, soft plastic, hard plastic, steel 304, steel 316, and steel 2379. The force and vibration signatures of shaft rub on bearing housing were analyzed. The results showed that the vibration amplitude of inboard bearing housing close to the motor increased significantly with the shaft speed increased. The spectrum for the soft plastic rub material found to has a unique characteristic so that the vibration level was lower than the baseline (without rub material) vibration.Öğe EVALUATION OF SURFACE ROUGHNESS IN DRILLING OF AA 7075 T6 PLATE WITH DIFFERENT CUTTING TOOL GEOMETRIES WITH EXPERIMENTAL, STATISTICAL AND DEFORM 3D SIMULATION(2022) Erkan, ÖmerThe basis of the study is to examine the average surface roughness (Ra) value resulting from drilling AA 7075 T6 plates with drills with different point angles (?) and under different cutting parameters. However, two different point angles (118° and 135°), three different cutting speeds (Vc) (40, 60 and 80 m/min) and three different feeds (f) (0.04, 0.08 and 0.12 mm/rev) were preferred in the experiments. The effect of cutting and tool geometry parameters on Ra was digitized by performing an ANOVA analysis. It was determined that Ra increased with the increase of Vc, ? and f. The parameter with the most significant effect on Ra was Vc with 49.10%, followed by ? with 30.52% and f with 13.67%, respectively. In order to examine the reasons for the increase in Ra value more effectively, drilling simulations were carried out under different cutting parameters using Deform 3D software. The simulation estimated temperature, cutting force and damage during drilling. The predicted results and the factors on Ra were revealed. In the experiments carried out with the drill with a tip angle of 135°, it was estimated that the temperature, the temperature, the cutting force and the damage value along the Z-axis were higher than the drill with a tip angle of 118°.Öğe Evaluation of the Relationship of Surface Roughness with Machining Parameters in Milling of AA 7075 Material with Experimental and Deform 3D Simulation(2023) Erkan, ÖmerAA 7075 T6 material offers important strength values and is easy to machining. In this respect, it is preferred on a wide scale in the industry. This study aimed to investigate the surface quality that occurs in the end milling of AA 7075 T6 material. For this, 3 different cutting speeds (40, 80, 120 m/min), three different feed rates (0.04, 0.08, 0.12 mm/rev), 2 different cutting depths (1 and 2 mm) were selected. The selected cutting parameters are combined with 2 and 4-flute end mills. As a result of the experiments, the average surface roughness (Ra) value was measured. The relations of Ra values with the cut parameters were determined. It was determined that Ra increased with increasing feed rate and decreased with increasing cutting speed. No significant effect of depth of cut was detected. Increasing the number of mouths increased Ra. The milling simulation was performed with the 3D cutting module in the Deform 3D software. 2 and 4 flute end mills are modeled, and the workpiece is defined to the software and the cutting parameters. Temperature, damage, stress, and cutting force outputs were estimated through simulations run at different cutting parameters. The predicted outputs and the experimental Ra outputs were interpreted and interpreted. Experimental outputs were supported by successfully applying milling simulation in Deform 3D software.Öğe Investigation of Surface Morphology of Drilled Cfrp Plates and Optimization of Cutting Parameters(World Scientific Publishing Co. Pte Ltd, 2020) Erkan, Ömer; Sur, Gökhan; Nas, EnginIn this study, the carbon fiber reinforced polymer (CFRP) composite material was drilled using different parameters (118° and 140° Point Angle, 30, 60 and 90m min-1 cutting speed and 0.06, 0.08 and 0.10mmrev-1 feed rate). Experimental parameters were designed according to full factorial design method and the results were analyzed using Taguchi L18 experimental design. The results of the study show that the lowest surface roughness values are 0.1958 and 0.1945?m with the cutting speed of 90 mmin-1 and feed rate of 0.06mrev-1 in the Point angles of 11° and 140°, respectively. When the results of Anova analysis were evaluated, parameters (feed speed, cutting speed and end point angle) according to the effect ratios on surface roughness were formed at the rates of 41.06%, 33.13% and 5.07%, respectively. The most suitable parameters according to S/N ratios were determined using A2B3C1 factors for the average surface roughness. © 2020 World Scientific Publishing Company.Öğe Optimization of Cutting Conditions, Parameters, and Cryogenic Heat Treatment for Surface Roughness in Milling of NiTi Shape Memory Alloy(Springer, 2022) Altaş, Emre; Erkan, Ömer; Özkan, Derviş; Gökkaya, HasanThis study discusses the milling of Nickel-Titanium (NiTi) alloy, one of the innovative and widely used shape memory alloy (SMA). During the face milling operations, the average surface roughness (R-a) was investigated depending on the change in machining parameters, cutting conditions, and cryogenic heat treatment. Experiments were carried out with uncoated and two different coated (PVD, CVD) cutting tools with untreated, shallow (- 80 degrees C) and deep (- 196 degrees C) cryogenic heat treatment. In addition, experiments were carried out using Ethylene Glycol (EG), and boron added Ethylene Glycol (EG+5%BX) cutting fluids as well as dry cutting condition. In the cutting experiments, three different cutting speeds (20-35-50 m/min), three different feeds (0.03-0.07-0.14 mm/tooth), and 0.7 mm fixed cutting depth was used as machining parameters. In the milling mechanism of NiTi shape memory alloys, how the cutting parameters affect the surface quality is discussed in detail. In this context, the cutting parameters were successfully optimized using Taguchi and ANOVA methods. The study is innovative in terms of evaluating the effect of different cutting fluids and cryogenic heat treatment. The results showed that CVD-coated cutting tool, - 196 degrees C cryogenic heat treatment, EG+5%BX cutting fluid, 50 m/min cutting speed, and 0.03 mm/tooth feed are the optimal parameters for the minor surface roughness. In addition, it has been determined that progress is the most influential parameter. On the other hand, ANOVA results showed that the most significant variable on the R-a was feed rate with 42.99%, and then cutting tool type 20.27%, cutting fluid 20.25%, cutting speed 11.68%, and cryogenic heat treatment 1.95%, respectively.Öğe Prediction of Damage Factor in end Milling of Glass Fibre Reinforced Plastic Composites Using Artificial Neural Network(Springer, 2013) Erkan, Ömer; Işık, Birhan; Çiçek, Adem; Kara, FuatGlass fibre reinforced plastic (GFRP) composites are an economic alternative to engineering materials because of their superior properties. Some damages on the surface occur due to their complex cutting mechanics in cutting process. Minimisation of the damages is fairly important in terms of product quality. In this study, a GFRP composite material was milled to experimentally minimise the damages on the machined surfaces, using two, three and four flute end mills at different combinations of cutting parameters. Experimental results showed that the damage factor increased with increasing cutting speed and feed rate, on the other hand, it was found that the damage factor decreased with increasing depth of cut and number of the flutes. In addition, analysis of variance (ANOVA) results clearly revealed that the feed rate was the most influential parameter affecting the damage factor in end milling of GFRP composites. Also, in present study, Artificial Neural Network (ANN) models with five learning algorithms were used in predicting the damage factor to reduce number of expensive and time-consuming experiments. The highest performance was obtained by 4-10-1 network structure with LM learning algorithm. ANN was notably successful in predicting the damage factor due to higher R-2 and lower RMSE and MEP.Öğe Selection of optimal machining conditions for the composite materials by using Taguchi and GONNs(Elsevier Sci Ltd, 2014) Erkan, Ömer; Demetgül, Mustafa; Işık, Birhan; Tansel, İbrahim NurMilling has been widely used in industry for machining parts to their final dimensions without requiring additional operations. Extensive experimental work is necessary to determine the optimal cutting conditions of glass-fiber reinforced polymer composite (GFRP) materials to achieve the desired surface quality. In this study, a series of machining operations were done for data collection by varying the flute number, feed rate, depth of cut and cutting speed. The relationship between the cutting parameters of end milling operations and the surface roughness of the machined surface was studied. For the analysis of the data and selection of the optimal cutting parameters the Taguchi method and genetically optimized neural network systems (GONNs) were used. Published by Elsevier Ltd.Öğe Stewart Platformu Esaslı Bir Takım Tezgahı İçin Alternatif Mafsal Tasarımı Ve Kinematik Analizi(2019) Erkan, ÖmerStewart platformları endüstride bir çok alanda kullanılmaktadır. Takım tezgahı olarak kullanılmaları ise sonyıllarda ön plana çıkmaktadır. Birçok tezgah üreticisi daha hassas ve işlevsel olan bu yapıdaki takım tezgahlarınaraştırma ve geliştirme faaliyetlerini sürdürmektedir. Yapılan çalışmada 6x6 Stewart esaslı takım tezgahıtasarımının 3B modeli oluşturulmuştur. Oluşturulan modelde alternatif bir mafsal tasarımı gerçekleştirilmiştir.Alternatif mafsalın mevcut durumda kullanılan ve maliyeti yüksek olan küresel mafsallara göre düşük olanmaliyetiyle ön plana çıktığı ve kolayca uygulanabildiği ifade edilmiştir. Bunun yanı sıra Stewart esaslı takımtezgahının istenen sabit ve hareketli platform çaplarıyla beraber istenen koordinat bilgilerine göre ters kinematikyöntem kullanarak uzuv boylarını hesaplayabilen bir yazılım geliştirilmiştir. Geliştirilen yazılımda çeşitlikoordinat verileri için uzuv boyları hesaplanmıştır. Alternatif mafsal tasarımı 3B tezgah modeline başarıylabütünleştirilirken, uzuv boyları da geliştirilen yazılımda başarıyla hesaplanmıştır.
