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Öğe AISI 1.2738 Çeliğinin Elektro-Erozyon Tezgahında Bakır ve Grafit Elektrot İle İşlenmesinde İşleme Parametrelerinin Yüzey Pürüzlülüğü Üzerine Etkisinin Deneysel ve İstatiksel Olarak İncelenmesi(2018) Nas, Engin; Argun, Kudbeddin; Zurnacı, ErmanBu çalışmada, AISI 1.2738 malzemenin farklı işleme parametrelerinde elektro erozyon tezgahında bakır ve grafitelektrot ile aşındırma işlemi gerçekleştirilmiştir. Kullanılan aşındırma parametreleri yapılan ön deneylersonrasında üç farklı vurum süresi (100, 200 ve 300 µs), bekleme süresi (10, 20 ve 30 µs) ve boşalım akım (10, 20ve 30 amper) olarak belirlenmiştir. Sinyal/Gürültü oranları ile belirlenen yüzey pürüzlülük değerinin optimumdeğerleri, vurum süresi için Seviye 1 (100 µs), bekleme süresi için Seviye 2 (30 µs), amper için Seviye 1 (10 A)ve elektrot için Seviye 2 (Grafit), anova sonuçlarına göre ise yüzey pürüzlülüğü üzerine en etkili parametrelerinsırası ile amper, vurum süresi, bekleme süresi ve elektrot olarak tespit edilmiştir.Öğe AISI 1.2738 Çeliğinin Elektro-Erozyon Tezgahında Grafit Elektrot ile İşlenmesinde İşleme Parametrelerinin Yüzey Pürüzlülüğü Üzerine Etkisinin İncelenmesi(2018) Nas, Engin; Argun, Kudbeddin; Zurnacı, ErmanBu çalışmada, AISI 1.2738 malzemenin farklı işleme parametrelerinde elektro erozyon tezgahında grafit elektrot ile aşındırma işlemi gerçekleştirilmiştir. Deneysel çalışmada kullanılan parametreler yapılan ön deneyler sonrasında üç farklı vurum süresi (100, 200 ve 300 µs), bekleme süresi (10, 20 ve 30 µs) ve boşalım akım (10, 20 ve 30 amper) olarak belirlenmiştir. Yapılan çalışmanın sonucunda en düşük yüzey pürüzlülük değerinin 100 µs vurum süresi, 10 µs bekleme süresi ve 20 amper akımda gerçekleştiği, en yüksek yüzey pürüzlülük değerinin ise 300 µs vurum süresi, 10 µs bekleme süresi ve 30 amper akımda gerçekleştiği belirlenmiştir.Öğe AISI 304 Paslanmaz Çelikte Geliştirilmiş Yüzey Kalitesi ve Azaltılmış Kerf Genişliği için Lazer Kesim Parametrelerinin optimizasyonu(2023) Nas, Engin; Uzuner, SabriBu çalışmada, yaygın olarak kullanılan bir lazer kesme makinesi kullanılarak AISI 304 paslanmaz çeliğin kesilmesi üzerine deneysel ve istatistiksel analizler gerçekleştirdik. Kesme parametreleri olarak üç farklı gaz basıncı 5.1, 6.4 ve 8 bar) , üç farklı kesme hızı (2048, 2560 ve 3200 mm/dak), sabit odak noktası (-4 mm), sabit frekans (5000 Hz) ve sabit gaz (Azot) kullanılmıştır. Yapılan çalışmanın sonucunda Bütün basınç değerlerinde kesme hızı arttıkça yüzey pürüzlülük değerinin azaldığı, bütün kesme hızı değerlerinde basınç arttıkça yüzey pürüzlülük değerinin arttığı görülmüştür. Kesme hızının artması ve gaz basıncının azalması ile üst ve alt kerf genişliğinin azaldığı, gaz basıncının artması ve kesme hızının azalması ile üst ve alt kerf genişliğinin arttığı belirlenmiştir. Taguchi analizi sonucunda sinyal/gürültü oranları incelendiğinde optimum kesme parametresinin basınç için Seviye 1 (5.1 bar) ve kesme hızı için Seviye 3 (3200 mm/dak.) olarak hesaplanmıştır. Varyans sonuçları incelendiğinde basınç ve kesme hızı faktörlerinden yüzey pürüzlülüğü değerine etki eden önemli parametrenin %70.74 ile kesme hızı olarak oluştuğu tespit edilmiştir.Öğe An Evaluation on the Reproducibility of Composite Materials Produced(Zonguldak Bülent Ecevit Üniversitesi, 2013) Nas, Engin; Gökkaya, Hasan; Sur, GökhanResearchers unceasingly continuetrying to improve the strength features of industrial materials to meet day to day increasing industrial needs. Most of these studies are on the improvement of composite materials. These materials constitute a group of materials which can not be separated from traditional ones. Composite is a mixed-structured material which is created by the addition of fiber, whisker, flake, particle etctothetraditional materials like metal, ceramic, plasticand refractor. Composites a reproduced in three ways depending on anaphases’ state; liquid, solidand solid-liquid. Today, powder metallurgy- one of the solids tatefabricationtechniques- is commonly used for the production of composites. In this study, the effects of hot pressingmethod used in powder metallurgy on the producibility of composites are evaluated.Öğe Analysis of the electrical discharge machining (EDM) performance on Ramor 550 armor steel(Carl Hanser Verlag, 2020) Nas, EnginThis study investigated the electrical discharge machining (EDM) performance of Ramor 500 Armor steel, a material used in the defense industry for armor production. In addition, the surface quality and amount of material wear of the treated surfaces were determined using different electrical discharge processing parameters for a copper electrode including pulse on-time (99, 150, 225, 300, 351 mu s), pulse off-time (10, 15, 23, 30, 35 mu s), and discharge current (3, 4, 6, 8, 9 A), at a constant pressure of 1 mm depth of cut. As a result of the experiments, the values related to the material removal rate (MRR) and the surface roughness (Ra) were obtained and the findings analyzed via response surface methodology (RSM). The increase in amperage and pulse on-time resulted in an increase in Ra and MRR values. The minimum and maximum Ra and MRR values emerged at currents of 3 and 9 A, respectively. In the experiments performed applying currents of between 3 and 9 A, the white layer widths were measured as 0.0474 mm and 0.0915 mm, respectively. The statistical test results showed that the most effective processing parameters for the MRR were the discharge current amperage (49.01 %) and the pulse off-time (16.51 %), whereas the most effective parameter for the Ra value was the discharge current amperage (79.07 %).Öğe CNC TORNALAMA İŞLEMİNDE YÜZEY PÜRÜZLÜLÜĞÜ VE KESME KUVVETLERİNE ETKİ EDEN PARAMETRELERİN MATEMATİKSEL OLARAK MODELLENMESİ(Düzce Üniversitesi, 2014) Özlü, Barış; Demir, Halil; Nas, EnginBu çalışmada; 30MnVS6 mikro alaşımlı çeliğinin tornalanmasında, kesme hızı (V) ve ilerleme miktarının (f) yüzey pürüzlülüğü (Ra) ve kesme kuvvetleri (Fc) üzerindeki etkileri ortaya konmuştur. Elde edilen yüzey pürüzlülüğü ve kesme kuvvetleri değerlerinin, kesme parametreleri ile olan ilişkilerinin matematiksel olarak modellenmesi için çeşitli eğri uydurma algoritmaları kullanılmıştır. Kullanılan bu eğri uydurma algoritmalarından elde edilen matematiksel modeller, korelasyon katsayıları (R2) kullanılarak değerlendirilmiştir.Öğe Davlumbazlarda Kullanılan Komponent Özelliklerinin Enerji Tüketimi ve Çalışma Performansı Üzerine Etkisinin Deneyselİstatiksel Olarak İncelenmesi(2020) Özbakış, Yusuf; Nas, EnginBu çalışmada mutfak davlumbazlarında kullanılan, motor ve filtrelerin ürün performans ve enerji tüketimiüzerine etkileri deneysel ve istatiksel olarak incelenmiştir. Bu amaç için mutfaklarda kullanılan iki farklı boyutasahip piramit tipi, davlumbaz seçilmiştir. Deneylerin gerçekleştirilmesi için iki farklı boyutta (60–90 cm) gövde,iki farklı özellikte motor (450-650 m3/h) ve iki tip filtre (3-5 katman) konfigürasyonuna sahip davlumbazlarınüretimi yapılmıştır. Çalışmanın deneysel tasarımı Taguchi L8 dizilimi kullanılarak oluşturulmuş ve deneylergerçekleştirilmiştir. Deney sonuçları incelendiğinde, 60cm boyuta sahip davlumbazların yıllık enerji tüketimi(AEC) en düşük 43,6 kWh iken en yüksek 62,7 kWh olduğu ve 90cm boyuta sahip davlumbazların ise en düşük48,7 kWh iken en yüksek 63,0 kWh olduğu görülmüştür. Filtrelerin yağ tutma verimliliği incelendiğinde endüşük yağ filtre verimliliği %68,4 olarak 90 cm boyuta sahip davlumbazda ve en yüksek %80,6 olarak 60 cmboyuta sahip davlumbazda oluşmuştur. Deneysel sonuçların istatiksel olarak incelenmesinde Sinyal/Gürültüoranları, Anova ve Regresyon analizleri kullanılmıştır. Sinyal/Gürültü oranları incelendiğinde en verimlinoktadaki debi (QBEP), yıllık enerji tüketimi (AEC), maksimum devirde hava akışı, gürültü performansı (LWA) veyağ filtresi verimliliği (GFE) için en ideal seviyeler sırası ile A2B2C2, A1B1C2, A2B2C2, A2B2C1 ve A1B2C1 olarakbelirlenmiştir. Anova sonuçları incelendiğinde QBEP, AEC, maksimum devirde hava akışı ve LWA için en etkiliparametrenin sırası ile %96,62, %93.02, %98,87, %41,45 oranla motor , yağ filtresi verimliliği için en etkiliparametrenin ise %62,72 oranla filtre katmanı olduğu tespit edilmiştir.Öğe Effect of machinability, microstructure and hardness of deep cryogenic treatment in hard turning of AISI D2 steel with ceramic cutting(Elsevier, 2020) Kara, Fuat; Karabatak, Mustafa; Ayyildiz, Mustafa; Nas, EnginThis study examined the hard turning of AISI D2 cold work tool steel subjected to deep cryogenic processing and tempering and investigated the effects on surface roughness and tool wear. In addition, the effects of the deep cryogenic processes on mechanical properties (macro and micro hardness) and microstructure were investigated. Three groups of test samples were evaluated: conventional heat treatment (CHT), deep cryogenic treatment (DCT-36) and deep cryogenic treatment with tempering (DCTT-36). The samples in the first group were subjected to only CHT to 62 HRc hardness. The second group (DCT-36) underwent processing for 36 h at -145 degrees C after conventional heat treatment. The latter group (DCTT-36) had been subjected to both conventional heat treatment and deep cryogenic treatment followed by 2 h of tempering at 200 degrees C. In the experiments, Al2O3 + TiC matrix-based untreated mixed alumina ceramic (AB30) and Al2O3 + TiC matrix-based TiN-coated ceramic (AB2010) cutting tools were used. The artificial intelligence method known as artificial neural networks (ANNs) was used to estimate the surface roughness based on cutting speed, cutting tool, workpiece, depth of cut and feed rate. For the artificial neural network modeling, the standard back-propagation algorithm was found to be the optimum choice for training the model. Three different cutting speeds (50, 100 and 150 m/min), three different feed rates (0.08, 0.16 and 0.24 mm/rev) and three different cutting depths (0.25, 0.50 and 0.75 mm) were selected. Tool wear experiments were carried out at a cutting speed of 150 m/min, a feed rate of 0.08 mm/rev and a cutting depth of 0.6 mm. As a result of the experiments, the best results for both surface roughness and tool wear were obtained with the DCTT-36 sample. When cutting tools were compared, the best results for surface roughness and tool wear were obtained with the coated ceramic tool (AB2010). The macroscopic and micro hardness values were highest for the DCT-36. From the microstructural point of view, the DCTT-36 sample showed the best results with homogeneous and thinner secondary carbide formations. (C) 2019 The Authors. Published by Elsevier B.V.Öğe Experimental and statistical investigation of electro-erosion machining performance of cryogenic treated hardened AISI H13 hot work tool steel(Elsevier Sci Ltd, 2024) Nas, EnginThis study investigated the machinability of AISI H13 hot work tool steel with a hardness of 54 HRC, which has been deep cryogenically treated using the electro-erosion machining technique, one of the unconventional manufacturing methods. The machinability parameters used in the study were determined as current (4, 8 and 12 A), pulse time (200, 300 and 400 mu s) and three different electrodes (Copper, Graphite and Tuncop). The experimental design was designed according to the Taguchi L27 model, and machinability tests were carried out to examine the results obtained from the experimental study both experimentally and statistically. When the literature was examined, it was seen that cryogenic treatment was generally applied to electrode materials, and only surface roughness and material wear amounts were examined as output parameters. The original value of the study is the interpretation of the results by applying cryogenic treatment to the test material and exploring the surface roughness and material wear amount, as well as the hole diameters and criterion diameters formed on the treated surfaces after the EDM process. As a result of the study, it was observed that the surface roughness value, the hole diameter, the amount of material wear, and the crater diameter increased with the increase in ampere and impact time. The lowest surface roughness value was 2.266 mu m in the graphite electrode material at 4 amps and 200 mu s impact time and the highest wear amount was realized as 0.555 g in the copper electrode material 12 amps and 400 mu s impact time. The smallest hole diameter was 12.254 mm with a tuncop electrode with a pulse duration of 4 amps and 200 mu s, and the lowest crater diameter was 127.301 mu m with a graphite electrode at a current of 4 amps and a pulse duration of 200 mu s. When the signal-to-noise ratios were examined, the optimum machining parameters for surface roughness, hole diameter, material wear amount, and crater diameter were determined as A2B1C1, A1B3C3, A3B1C1, and A3B1C1, respectively. When the ANOVA results are examined, it is determined that the most effective parameter for the surface roughness is of the current value with 86.54%, the most effective parameter for the hole diameter is the electrode material with 85.20%, the most effective parameter for material wear amount is the electrode material with 45.67% and the most effective parameter for the crater diameter is current value with 75.35%.Öğe Experimental and Statistical Investigation of Machinability of AISI D2 Steel Using Electroerosion Machining Method in Different Machining Parameters(Hindawi Ltd, 2021) Nas, Engin; Ozbek, Onur; Bayraktar, Furgan; Kara, FuatThis study investigated the effects of machining parameters on the experimental and statistical results using the electric discharge method in the machining of AISI D2 cold work tool steel. The design of the experiment was established using the Taguchi L-18 method. The effect of the experiment parameters on the performance characteristics was analyzed by analysis of variance (ANOVA). As a result of the study, it was determined that increasing amperage and pulse time affected the surface roughness and hole diameter on the surface of the material. The lowest values for surface roughness, machining time, hole diameter, and crater diameter were determined as 2.085 mu m, 47 minutes, 12.010 mm, and 81.007 mu m, respectively. The highest wear amount was obtained as 0.604 grams with the processed parameters in the ninth experiment. When the signal-to-noise ratios were examined, the optimum combinations of the control factors for surface roughness, hole diameter, crater diameter, wear amount, wear rate, and processing time were determined as A(1)B(1)C(3), A(1)B(1)C(3), A(1)B(1)C(3), A(1)B(3)C(1), A(2)B(1)C(1), and A(1)B(3)C(3), respectively. According to the ANOVA results, the most important parameters affecting the test results for surface roughness, hole diameter, crater diameter, wear amount, material wear loss, and processing time were determined as amperage (49.34%), time-on (59.38%), amperage (55.65%), time-on (56.92%), amperage (51.42%), and amperage (78.02%), respectively. When the gray relational degree was calculated for the maximum and minimum values, the ideal factors for all output results were found to be the parameters applied in the third experiment.Öğe Experimental and Statistical Study on Machinability of the Composite Materials with Metal Matrix Al/B4C/Graphite(Springer, 2017) Nas, Engin; Gökkaya, HasanIn this study, four types of Al/B4C/Graphite metal matrix composites (MMCs) were produced by means of a hot-pressing technique with reinforcement elements, B4C 8 wt pct and graphite (nickel coated) 0, 3, 5, and 7 wt pct. Machinability tests of MMC materials thus produced were conducted using four different cutting speeds (100, 140, 180, and 220 m/min), three different feed rates (0.1, 0.15, and 0.20 mm/rev), and a fixed cutting depth (0.5 mm), and the effects of the cutting parameters on the average surface roughness were examined. After the machinability tests, the height of the built-up edge (BUE) formed on the cutting tools related to the cutting speed and feed rate was measured. The test results were examined by designing a matrix according to the full factorial design and the average surface roughness, and the most important factors leading to formation of the BUE were analyzed by the analysis of variance (ANOVA). As a result of analysis, it was found that the lowest surface roughness value was with 7 wt pct graphite MMC material, while the highest was without graphite powder. Based on the statistical analysis results, it was observed that the most important factor affecting average surface roughness was the type of MMC material, the second most effective factor was the feed rate, and the least effective factor was the cutting speed. Furthermore, it was found that the most important factor affecting the formation of the BUE was the type of MMC material, the second most effective factor was the cutting speed, and the least effective factor was the feed rate.Öğe Investigation of Drilling Performance of Hardened 32CRMOV12-10 Tool Steel on Electro EDM Machine(Düzce Üniversitesi, 2023) Bedir, Gökhan; Nas, EnginIn this study, EDM process was applied to 32CrMoV12-10 (1.7765) high-quality cold work tool steel with a hardness of 50 HRC with different processing parameters. The experimental design of the study was prepared using Taguchi L27 orthogonal array. Processing parameters were used three different electrode materials (copper, graphite, tuncop), three different currents (10, 20, 30 A), three different pulse durations (200, 400, 600 µs), constant cutting depth (1 mm) and constant time off (50 µs). Following the experiments, the hole diameters formed by the electrode materials on the material surface were measured. The results obtained were examined experimentally and statistically. The smallest hole diameter was measured as 12.2085 mm in the experiments carried out with the copper electrode, and the largest hole diameter was measured as 12.5284 mm with the tuncop electrode. When the study was examined statistically (Signal-to-noise ratio), it was determined that the most suitable processing parameters to create the ideal hole diameter were 10 A ampere current and 200 µs pulse duration in copper electrode material. When the analysis of variance (ANOVA) results were examined, it was determined that the most effective machining parameter for the hole diameter was the ampere value of 47.85%.Öğe Investigation of Electro-Discharge Driling Performance of 32CRMOV12-10 Steel(Düzce Üniversitesi, 2022) Bedir, Gökhan; Nas, EnginIn this study, machining of 32CrMoV12-10 steel was carried out using the electro-erosion machining method at different machining parameters. The experimental design of the study was created using the Taguchi L27 array, and three different electrode materials, three different amperes (10, 20, 30 A) and three different impact times (200, 400, 600 µs), fixed depth of cut (1 mm) and dwell. (50 µs) processing parameters were used. After the experiments carried out, the measurements of the hole diameters formed by the electrode materials on the material surface were made and the results obtained were examined experimentally and statistically. As a result of the study, it was determined that the lowest hole diameter formation occurred at 200 µs and 10 ampere current in the experiments performed with all electrode materials, and the largest hole diameter occurred at 600 µs and 30 ampere current in all electrode materials. Among the electrode materials, the smallest hole diameter was 12,2101mm in copper material and the largest hole diameter was 12,6551mm in graphite material. When the signal-to-noise ratios are examined statistically, the optimum processing parameter for the ideal size of the hole diameter was determined as copper for the electrode material, 10 A for the amperage value and 200 µs for the pulse duration. When the analysis of variance (ANOVA) results were examined, it was determined that the most effective machining parameter on the hole diameter was 69,72% of the impact time.Öğe Investigation Of Electroerosion Machining Performance Of Metal Matrix Composite Materials Produced Using Stir And Indirect Squeeze Method(World Scientific Publ Co Pte Ltd, 2023) Ugur, Abdullah; Nas, Engin; Gokkaya, HasanIn this study, metal matrix composite (MMC) materials were made with an aluminum matrix (AA7075 alloy) and reinforcement silicon carbide (SiC) elements using molten metal stir and indirect squeeze casting. SiC was used as a reinforcing element in the making of MMC material in different amounts (10%, 14%, and 18%) by mass. Electro Discharge Machining (EDM), cut depth (0.5 mm), three different pulse-on times, three different discharge current values, and a fixed pulse-off time (20 s) were used to machine MMC materials. The effects of machining parameters on machining time, average surface roughness, hole diameter, and material wear difference after machining were studied. As a result of the study, the composite material with 75 mu s pulse-on time, 6A current value, and 10% reinforcement element had the lowest machining time, the largest hole diameter, and the smoothest average surface. These machining parameters and materials also had the shortest machining time (5 min). Based on the signal-to-noise ratios, the best parameters for average surface roughness, hole diameter, Processing time, and material wear amount (MMC, discharge current value, and impact time) were found to be L2L1L1, L3L1L1, L1L3L3, and L1L1L2, respectively. Based on the ANOVA results, the R2 values for the average surface roughness, hole diameter, machining time, and material wear loss value were 99.3%, 98.7%, 77.8%, and 97.3%, respectively.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 Investigation of the machinability of SiC reinforced MMC materials produced by molten metal stirring and conventional casting technique in die-sinking electrical discharge machine(Pergamon-Elsevier Science Ltd, 2020) Ugur, Abdullah; Nas, Engin; Gokkaya, HasanIn this study, MMC materials were produced by stir casting method using AA7075 alloy matrix and silicon carbide (SiC) as reinforcement elements in order to investigate the effect of die-sinking electric discharge machining (EDM) process parameters for various weight percentage reinforcement (10% 14% and 18%) used MMC. EDM with three different pulse-on time (Time on) (25, 50 &75 mu s) and discharge current value (2, 4 & 6 Amperes) and at constant dwell time (20 mu s) and depth of cut (0.5 mm). After machining process, the effects of process parameters on processing time, average surface roughness, hole diameter and the weight loss were investigated. As a result of the study, highest values, the lowest values of processing time, hole diameter and average surface roughness were obtained for various weight percentage reinforcement MMC respectively. Ideal MMC, discharge current value and time-on duration for average surface roughness, hole diameter, processing time and material wear loss according to signal to noise ratio were determined. According to ANOVA results, R-2 values for the average surface roughness, hole diameter, processing time and material wear loss were calculated as 89.55%, 98.46%, 89.85% and 24.06% respectively.Öğe Mechanical and physical properties of hybrid reinforced (Al/B4C/Ni(K)Gr) composite materials produced by hot pressing(Carl Hanser Verlag, 2015) Nas, Engin; Gökkaya, HasanIn this study, the mechanical and physical properties of hybrid reinforced (Al/B4C/Ni(K)Gr) metal matrix composite (MMC) materials were investigated. The MMC materials were produced using the powder metallurgy (PM) production method of hot pressing (HP). The aluminum alloy Alumix 13 was used as matrix material and boron carbide (B4C) and nickel-coated graphite (Ni(K) Gr) as reinforcement elements. The microstructural characteristics, hardness, 3-point bending strength and density values of the produced hybrid reinforced MMC materials were determined. The reinforcement element B4C was kept at constant concentration of 8 wt.-%. Four different MMC materials were produced with the addition of 0, 3, 5 and 7 wt.-% Ni(K) Gr in the B4C. From the SEM images of the MMC materials produced by the HP technique, it was observed that the reinforcement element exhibited a uniform distribution. Moreover, the particles showed an approach to each other depending on the particle size and the amount (wt.-%) of the reinforcement element. With increasing graphite content in the structure density, hardness and 3-point bending test values decreased.Öğe Merkezi Havalandırma Sistemlerine Uygun Mutfak Davlumbazına Eklenen Bariyerin Koku Çıkarma Performansına Etkisi(2020) Özbakış, Yusuf; Erzincanlı, Fehmi; Çeviksever, Tolga; Nas, EnginBu çalışmada, merkezi havalandırma sistemlerine uygun mutfak davlumbazına eklenen bariyerin koku çıkarma performansı üzerine etkileri araştırılmıştır. Bu amaç için merkezi havalandırma sistemlerine sahip binaların mutfaklarında kullanılan davlumbaz seçilmiştir. Davlumbazın koku çıkarma performansını optimize etmek vehem deneysel hem de istatiksel olarak incelemek için Taguchi L18 (61x31) deneysel tasarım yönteminden yararlanılmıştır. Seçilen yöntem ile farklı boyutta bariyere sahip mutfak davlumbazları oluşturulmuştur. Deneyler uluslararası standartlara uygun test odasında gerçekleştirilmiştir. Deney sonuçları incelendiğinde deneylerde oluşturulan davlumbazların koku çıkarma performansı en iyi %97,1 olduğu, en kötü %69,4 olduğu görülmüştür. Farklı boyutlara sahip bariyer ve debi parametreleri ile gerçekleştirilen deneylerin Sinyal/Gürültü oranları incelendiğinde C2 için en ideal seviyeler A6B3 olarak belirlenmiştir. Anova sonuçları incelendiğinde C2 için en etkili parametrenin %76,01 ile bariyer (cm) ve %21.24 ile debi (m3/h) olduğu tespit edilmiştir. Davlumbaza eklenen bariyer sayesinde daha yüksek koku çıkarma performansı sağlanmıştır.Öğe Optimization of EDM Machinability of Hastelloy C22 Super Alloys(Mdpi, 2022) Nas, Engin; Kara, FuatIn this study, machinability tests were carried out on a corrosion-resistant superalloy subjected to shallow (SCT) and deep cryogenic treatment (DCT) via electrical discharge machining (EDM), and the effect of the cryogenic treatment types applied to the material on the EDM processing performance was investigated. Experimental parameters, including pulse-on time (300, 400 and 500 mu s), peak current (A) (6 and 10 A) and material types (untreated and treated with SCT and DCT), were used to construct the full factorial experimental design. The resulting average surface roughness (Ra) and material removal rate (MRR) results were optimized using the Taguchi L-18 method. According to the Taguchi-based gray relational analysis, the optimal parameters for both Ra and MRR were determined as cryogenic treatment, pulse-on time and peak current, respectively. The response table obtained using the Taguchi method showed the most effective factors as A(1)B(l)C(3) for Ra and A(2)B(2)C(1) for MRR values. According to the ANOVA results for determining parameters affecting performance, peak current was the most effective factor for average surface roughness and MRR, at 74.79% and 86.43%, respectively. When examined in terms of Taguchi-gray relational degrees, the optimal parameters for both Ra and MRR were observed in the experiment performed with the SCT sample at a peak current of 6 A and 300 mu s pulse-on time.Öğe Optimization of surface roughness via the Taguchi method and investigation of energy consumption when milling spheroidal graphite cast iron materials(Carl Hanser Verlag, 2018) Nas, Engin; Öztürk, BurakDue to its excellent casting ability, spheroidal graphite cast iron is widely used in the production of complex automotive and machine products. In this study, the milling of spheroidal cast iron was carried out at different parameters. First, using the Taguchi statistical method, the parameters affecting surface roughness values were determined to b e cutting tool (65.54 %), then feed rate (19.65%), and finally, with a minimum effect, cutting speed (7.31%). Second, the amount of power consumed during chip removal was observed as being larger than the amount consumed when the machine was operating without a cutting load. Increases in the power index (PI) were measured by an amperemeter and it was determined that, as cutting speed was augmented, the amount of total power (P-total) consumed decreased, while, as feed rate was augmented, total power consumption increased. Total cutting energy (Pcutting) was increased by stepping up cutting speed. The PI was increased as a result of stepping up cutting speed and feed rate. On the basis of the cutting parameters, the Pcutting, P(total )spindle torque (%) and specific energy consumption (SEC) value changes were calculated.
