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Öğe Hardness and wear behaviours of al matrix composites and hybrid composites reinforced with B 4 C and SiC(Springer Nature, 2019-01-15) Çelik, Yahya Hışman; Kılıçkap, ErolThe conversion into the desired shape of the metal powders using Powder Metallurgy (PM) method enables economically mass productions. This case allows producing parts with complex and high dimensional accuracy with no machining. In this study the composites and hybrid composites with Al matrix were produced using PM method with different ratios B4C and SiC. Microhardness and wear experiments of the produced composites were investigated. Wear experiments were performed at a constant speed of 0.5 m/s, application loads of 5, 10 and 15 N and sliding distances of 250, 500, and 750 m. Then, SEM images of composites and hybrid composites were captured. The increase of the reinforcement ratio in the composites contributed to the increase of the hardness. The highest hardness value was computed as 58.7 HV from 16% B4C reinforced composite. In addition, the increase in the reinforcement ratio contributed to the increase of the wear resistance. The increase in the load and sliding distance also increased the wear. The minimum weight loss was calculated as 18 mg from 5 N load, 250 m sliding distance and 16% SiC reinforced composite.Öğe Investigation of mechanical properties of composites obtained from textile wastes(Batman Üniversitesi, 2022-07-02) Adin, Mehmet ŞükrüThe textile industry is one of the manufacturing sectors that pollutes the world the most. Since textile wastes are destroyed by burning traditionally, they cause great damage to the environment. Therefore, recycling of these wastes is of great importance. One of these recycling methods is their use in the production of composite materials, the application areas of which have increased in recent years. In this study, the mechanical properties of composite materials produced using cotton and polyester fabrics from waste textiles were investigated. It has been observed that 22% of the composite materials produced with reinforcement elements at different angles (0°, 45°, 90°) are reinforcement elements and 78% are resins. As a result of the tensile tests, the highest tensile strength value was obtained with the polyester fabric with 0° reinforcement angle as 55.72 MPa. It has been found that the increase in the reinforcement angles positively affects the tensile strength in cotton fabric reinforced composites, whereas this situation occurs in the opposite way in polyester fabric reinforced composites. When the highest tensile strength values of polyester fabric and cotton fabric reinforced composite samples were compared, it was seen that the sample using polyester fabric (55.72 MPa) had 69% higher tensile strength than the sample using cotton fabric (33.05 MPa). In addition, the elongation values of polyester fabric reinforced composites were higher than cotton fabric reinforced composites.Öğe Investigation of wear behaviours of Al matrix composites reinforced with different B4C rate produced by powder metallurgy method(Elsevier, 2017-09) Çelik, Yahya Hışman; Seçilmiş, KübraIn this study, the effects of wear behaviours of Al matrix composites reinforced with different B4C rate produced by powder metallurgy method were investigated. Al and B4C powders with purity of 99.9% and sizes of 25–44 µm were prepared as pure Al, 4% B4C/Al, 8% B4C/Al, 12% B4C/Al and 16% B4C/Al. After these prepared mixtures were pressed under 350 MPa, they were sintered for 90 min at 580 °C in atmospheric environment. Microhardness and wear tests of the produced samples were carried out. Wear experiments of these composites were performed with specially manufactured test equipment at different application loads (5 N, 10 N and 15 N), different sliding distances (250 m, 500 m, 750 m and 1000 m) and a constant speed of 0.46 m/s. In addition, optical microscope, SEM, EDS analyses were used to determine the microstructural changes in the worn and unworn surface of the manufactured composite materials. The results of experimental studies show that the increasing the B4C reinforced rate in composites with Al matrix has led to increase of the hardness and to reduce of the wear loss.Öğe Effects of natural hard shell particles on physical, chemical, mechanical and thermal properties of composites(SAGE Journals, 2021-05-31) Çelik, Yahya Hışman; Çelik, Kadir Serdar; Kılıçkap, ErolShelled herbal foods are widely consumed. The evaluation of the shells of these foods is important due to their features such as low cost, ease of recycling and environmental friendliness. In this study, hazelnut shell (HS), pistachio shell (PS), and apricot kernel shell (AKS) were brought to powder particles by grinding to dimensions of 300–425 µm. Some of the powder particles were converted into ash at 900°C. The amounts of cellulose, ash, humidity, and metal in these particles via chemical analyses were determined, while their structural properties via X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) analyses. Composite materials were produced by adding 15 wt.% to the polyester matrix material from these powder particles and ashes. Compression strength, hardness, specific weight, and thermal conductivity of these composites were analyzed. The lowest and highest humidity, ash, cellulose, hemicellulose, and lignin ratios in powders showed differences depending on the type of powders. The amount of Sn and K in the HS, PS, and AKS powders were close to each other, while the amount of Ca, Na, Mg, Fe, Mn, Cu, Zn and Si was higher in AKS powder. The reinforcement adding to the polyester increased the compression strength, hardness, specific weight and thermal conductivity properties.Öğe Numerical investigation of fatigue behaviors of non-patched and patched aluminum pipes(Hibetullah KILIÇ, 2021-06-01) Adin, Hamit; Yıldız, Bilal; Adin, Mehmet ŞükrüIn this study, the fatigue behaviors of non-patched and patched aluminum pipes were investigated numerically. The Finite Element Method was used for fatigue analysis in the study. Finite Element Method was implemented with Ansys Workbench (15.0) program. Al 6063 type aluminum pipe, DP-460 type adhesive and [0/90]2 reinforced angled glass-epoxy composite patch material were used in the analyzes. As a result of the numerical study, it was observed that patch size is an effective parameter in fatigue strength and that quarter-circle and semi-circular composite patches increase the fatigue life. It was also observed in the analyzes that the quarter-circle patched aluminum pipes achieved higher fatigue strength.Öğe Numerical investigation of fatigue behavior of non-patched and patched aluminum/composite plates(Ahmet ÇALIK, 2021-12-20) Adin, Hamit; Sağlam, Zeyni; Adin, Mehmet ŞükrüIn this study, the fatigue behavior of composite patched and non-patched Al 5083 aluminum plates was numerically investigated. Al 5083 Aluminum plates with semi-circular notched (2, 3 and 4 mm long cracked) and "V" notched (30°, 45° and 60° angled) were used in the analyzes. Mechanical properties of Al 5083 Aluminum plate, DP460 type adhesive of produced by 3M and [0°]8 glass fiber reinforced composite patch material was used for the study. The Finite Element Method was applied for numerical study. Numerical analyzes were performed with the Ansys version 15.0 Workbench Package program. As a result of the numerical study, the highest fatigue life (1593.2 N) is seen on the 30° angled "V" notched and patched specimen. However, the fatigue life in non-patched specimen (30° angled "V" notched) was found to be 277.69 N. Thus, the study revealed that the composite patch's contribution is very important.Öğe Investigation of wear behavior of aged and non-aged SiC-reinforced AlSi7Mg2 metal matrix composites in dry sliding conditions(SpringerLink, 2020-01) Çelik, Yahya Hışman; Kılıçkap, Erol; Demir, Mehmet Emin; Kalkanlı, AliMetal matrix composites (MMCs) with their splendid mechanical properties have been specifcally designed for use in felds such as aerospace and aviation. The presence of hard ceramic particles in MMC increases the hardness of the matrix product and decreases its coefcient of friction. Therefore, the wear resistance is improved. Moreover, the mechanical properties of these composite materials can be improved by applying heat treatments. In this study, AlSi7Mg2 MMCs with 15 wt% SiC reinforcement were produced by squeeze casting technique. Some of the composites were aged by heat treatment. Hardness values of aged and non-aged composites were compared. In addition, abrasive wear behaviors of these composites were investigated on pin-on-disk device, depending on the load (7, 12 and 17 N), the sliding speed (0.2, 0.3 and 0.4 m/s) and the sliding distance (700, 1000 and 1300 m). Worn surfaces were also analyzed by scanning electron microscopy (SEM). As a result of the analyses, it was determined that both the hardness values and the wear resistance were higher in the composites subjected to aging treatment. Furthermore, it was observed that the increase in the applied load led up to the weight loss. The increase in the sliding distance increased both friction coefcient and weight loss. The increase in sliding speed also made way for the friction coefcient but ensured less weight loss. When SEM images were examined, it was ascertained that deformation and tribo-surface formation had a signifcant efect on weight losses.Öğe Optimization of mechanical properties of composites obtained from textile wastes using Taguchi and ANOVA methods(Batman Üniversitesi, 2022-07-02) Adin, Mehmet ŞükrüToday, one of the most polluting manufacturing sectors is the textile industry. Therefore, recycling of these wastes is of great interest. One of the solutions applied for the recycling of these wastes is their use in the manufacture of composites. In this study, optimization of manufacturing parameters was made in order to obtain plates with the highest tensile strength from composite materials to be produced from textile wastes by using Taguchi and ANOVA methods. As a result of the study, it was found that the tensile strength of the composite plates made of polyester fabric was higher than the plates made of cotton fabric, and the signal/noise (S/N) ratios of 0° angle reinforced composites were lower than 90° angle reinforced composites. It was observed that there was a nearly linear increase in the S/N ratios depending on the increase in the number of reinforcements. As a result of the ANOVA analysis, it was found that the most effective factor according to the tensile strength was the reinforcement angle with 45.06%. It was observed that the highest tensile strength of the composite plates obtained from cotton fabric was 40.058 MPa with 90° angled reinforcement elements and 14 reinforcements, and the lowest tensile strength was 23.451 MPa with 0° angled reinforcement elements and 10 reinforcements. In composite plates obtained from polyester fabric, the highest tensile strength was 42.136 MPa with 45° angled reinforcement elements and 14 reinforcements, and the lowest tensile strength was 27.112 MPa with 0° angled reinforcement elements and 10 reinforcement numbers. It has been found that the tensile strength of the composite plates obtained from polyester fabric is higher than that of the composite plates obtained from cotton fabric.
