This study investigated the effects of FDM (Fused Deposition Modeling) process parameters on mechanical properties (tensile strength, elongation, and impact strength) of 3D (three-dimensional) printed PA12 (Polyamide12) samples using Taguchi method. In the experimental design (L8), four different layer thickness (0.1, 0.15, 0.2, 0.25 mm), extruder temperature (250 and 260°C), filling structure (Rectilinear and Full Honeycomb), and occupancy rate (25 and 50%) were determined. The tensile and impact strength test samples were printed with the FDM method. Tensile and impact strength of the test samples were carried out according to ISO 527 and ISO 180 test standards. The findings obtained from tests were analyzed and compared. As a result, the layer thickness is most effective factor for enhance the mechanical properties instead extruder temperature, occupancy rate, and filling structure. The optimum tensile strength of determined for process parameters (layer thickness, occupancy rates, filling structures and extruder temperature) were 0.25 mm, 50%, Rectilinear, and 250°C, respectively. The optimum impact strength of determined for process parameters (layer thickness, occupancy rates, extruder temperature, and filling structures) were 0.25 mm, 50%, 250°C, and Rectilinear, respectively. PA12 filament material can be used to printing for sleeve bearing due to their mechanical properties. It can be used in the production of many machine parts and components due to its tensile strength, impact strength resistance and damping properties.

No abstract

Additive Manufacturing (AM), widely known as three-dimensional (3D) printing, is the process that a product is fabricated layer by layer in Cartesian coordinate system. Fused Deposition Modelling (FDM) is the most used AM process for functional rapid prototyping and products reduces the time and material involved in manufacturing. The purpose of this study is to investigate the effects of 3D printer system vibrations on the surface roughness of fabricated products. Polyethyletherphthalate Glycol (PET-G) is used as material for fabrication. Six different filling structures -Rectilinear, Grid, Triangular, Wiggle, Fast Honeycomb, and Full Honeycomb -were used and for each structure two different top -two and three -layers implemented. A total of 12 samples specimens were fabricated. The results showed that using Full Honeycomb filling structure with three top layers is more suitable for surface roughness compare to the others filling structure used. It can be concluded that the vibration of 3D printer system considering type of filling structure and number of top layers have a significant effect on surface quality of product. ÖZETYaygın olarak üç boyutlu (3D) baskı olarak bilinen Eklemeli Üretim (Additive Manufacturing -AM), bir ürünün Kartezyen koordinat sisteminde katmanla üretildiği süreçtir. Erişim Birikim Modelleme (Fused Deposition Modeling -FDM), fonksiyonel hızlı prototipleme ve ürün için en çok kullanılan AM sürecidir, üretimle ilgili zamanı ve malzemeyi azaltır. Bu çalışmanın amacı, 3D yazıcı sistem titreşimlerinin, imal edilen ürünlerin yüzey pürüzlülüğü üzerindeki etkilerini araştırmaktır. Üretim için malzeme olarak Polietileterftalat Glikol (PET-G) kullanılmıştır. Altı farklı dolgu şekli -Rectilinear, Grid, Triangular, Wiggle, Fast Honeycomb ve Full Honeycomb -kullanılmış ve her yapı için iki farklı üst katmaniki ve üç katmanuygulanarak toplam 12 test numunesi basılmıştır. Basılan ürünlerin yüzey pürüzlülüğü ölçümleri yapılarak elde edilen veriler üzerinden karşılaştırma yapılmış ve sonuçlar analiz edilmiştir. Sonuçlar, üç üst katmanlı ızgara (Grid) doldurma yapısının kullanılması, yüzey pürüzlülüğü için diğer doldurma yapılarına kıyasla daha uygun olduğunu göstermiştir. Dolgu Düzce Üniversitesi Bilim ve Teknoloji Dergisi, 7 (2019) 147-157 şekli türüne ve üst katmanların sayısına bağlı olarak 3D yazıcı sisteminin titreşiminin ürünün yüzey kalitesi üzerinde önemli bir etkisi olduğu görülmüştür.

3D printing technology has gradually taken its place in many sectors. However, expected performance cannot be obtained from the structural parts with this method due to the raw material properties and constraints of Cartesian motion systems. This technology cannot replace structural parts produced by traditional manufacturing methods. In order to avoid these constraints, it is preferred to use continuous fiber reinforced polymer composites in many areas such as automotive and aerospace industries due to their low weight and high specific strength properties. These automated composite manufacturing methods currently have limited production of geometric shapes due to the need for additional molds and production as flat surfaces. To overcome all these constraints, fiberglass reinforced ultraviolet ray-curing polymer matrix composite material are selected for robotic 3 D printing process and various parameters are examined. Fiber-polymer combination and layer structure formation was examined. Scanning Electron Microscopy (SEM) images of sections of 3 D printed test samples were taken and fiber resin curing was examined. The nozzle diameter, printing speed, fiber density and Ultra Violet (UV) light intensity parameters, which will provide effective 3 D printing process, are optimized with the Taguchi method. Tensile strength, flexural strength and izod impact values are considered as result parameters for optimization. It was found that it would be appropriate for 3D printing with a 1.0 mm nozzle diameter, 600 tex fiber density, 4 UV light, 600 mm/min printing speed. With these 3D printing process parameters, approximately 125 MPa tensile strength and 450 MPa flexural strength can be obtained. With this study, support and contribution was provided to researchers, composite producers, tool manufacturer and literature who want to use and develop this 3D printing process.

Bu çalışmada, farklı doldurma şekillerinin Ergiyik Depolayarak Modelleme (Fused Deposition Modelling-FDM) yöntemi ile imal edilen ürünlerin mukavemetine etkisi deneysel olarak incelenmiştir. Çalışmada filament malzeme olarak PET-G (Polyethylene Terephthalate Glycol) kullanılmış ve farklı doldurma şekillerinde (Rectilinear, Grid, Triangular, Wiggle, Fast honeycomb, Full honeycomb), doluluk oranı (%30), işleme hızı (4200 mm/dak), nozul çapı (0,40 mm), nozul sıcaklığı (230 ºC), katman kalınlığı (0,20 mm) olmak üzere ISO 527-2 standardına uygun ürünler imal edilmiştir. Bu numunelerin çekme mukavemetlerini incelemek için çekme testleri gerçekleştirilmiş ve testlerden elde edilen sonuçlar karşılaştırılmıştır. Sonuçlar yazdırma şekillerinin ürün mukavemeti üzerinde önemli etkisi olduğunu göstermiştir. Rectilinear doldurma şeklinde imal edilen ürünlerde elde edilen mukavemet değerleri diğer doldurma şekillerine göre yaklaşık % 15 daha yüksek çıkmıştır. Ayrıca, Full honeycomb doldurma şeklinin diğer doldurma şekillerine göre daha fazla uzama gösterdiği görülmüştür.

In this study, it was realized to determine effects of Fused Deposition Modeling (FDM) process parameters on mechanical characteristics with Taguchi optimization method. Three different FDM process parameters used for modified Polylactic Acid (PLA+) filament material; filling structures (Rectilinear, Triangular, and Full Honeycomb), occupancy rates (10, 30, and 50 %) and table orientation (0, 60, and -45°) was specified as variable parameters for experiments.Other parameters kept fixed for each tensile and izod impact test samples were printed according to the ISO 527 -Type IV and ISO 180-Type I standards. The results found tensile strength values and izod impact values directly proportionate with occupancy rate. The difference between the estimation model and the results of experiments did not exceed the maximum value of 1.8 %. Thus, using the equations derived from this optimization, printing parameters can be determined for the desired tensile strength and izod impact values. By improving the material properties using modified PLA+ filament material as observed in the results, it will be possible to provide support for researchers, design engineers and manufacturer to optimize raw-material usage and margin.

Bu makaleye şu şekilde atıfta bulunabilirsiniz(To cite to this article): Kam M., Saruhan H. ve İpekçi A., "FDM yöntemi ile üretilen kovan yatakların titreşimi sönümleme kabiliyetlerinin deneysel analizi" Politeknik Dergisi, *(*): *, (*).

Electrical Discharge Machining (EDM) is commonly used as non-traditional manufacturing methods for geometrically complex shaped or hardened materials that are extremely difficult-to-machine with traditional machining processes. In this experimental study, investigations were carried out on the machining of Conventional Heat Treated three different deep cryogenically treated and tempering processes (DCT&T) of AISI 4140 steels in EDM process. The process parameter such as discharge current (9, 16, 23, and 30 A), pulse on time (120, 180, 240, 300 µs) and pulse off time (12, 18, 24, and 30 µs) were investigated and the output responses like surface roughness, electrode wear ratio, material removal rate, and machining time were explored. Experiments were conducted using L16 orthogonal array in EDM machining process. The data obtained from experiments were analyzed. As a result, determination of discharge current (30 Amps), pulse off time (12 to 18 µs), pulse on time (180 to 240 µs) and deep cryogenically treatment with 24 h and 48 h holding time as the optimum machining processing parameters for tempered steels to be subjected to DCT&T process. As a result of multi-criteria optimization, it is suitable for best surface quality and fast material removal rate.