Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2025
    Effect of sodium pentaborate (B5H10NaO13) nanoparticle addition to oxide coatings grown on AZ31 magnesium alloy by micro arc oxidation method on mechanical, corrosion and adhesion properties of coatings; [Efecto de la adición de nanopartículas de pentaborato de sodio (B5H10NaO13) en los recubrimientos de óxido formados sobre la aleación de magnesio AZ31 mediante el método de Microoxidación por Arco, sobre las propiedades mecánicas, de corrosión y de adhesión de los recubrimientos]

    Sukuroglu, Suleyman

    AZ31 magnesium alloy is one of the lightweight metallic engineering materials that are widely used in many industrial areas such as aviation, space, automobile and electronics industries, biomedical applications, where structural weight reduction is at the forefront of design principles. This study focuses on the growth of MgO and MgO:B5H10NaO13 doped oxide coatings on the surface of AZ31 magnesium alloy by micro arc oxidation (MAO) method in order to improve its usage areas and lifetime in industrial applications, and to investigate the structural, morphological, adhesion and corrosion properties of the grown coatings. In the study, MgO coatings were grown by MAO method and MgO:B5H10NaO13 doped composite oxide coatings were grown by adding sodium pentaborate (B5H10NaO13) nanoparticles into the electrolytic solution in MAO method. The phase structure of the grown coatings was determined by X-ray Diffraction (XRD), microstructure by Scanning Electron Microscopy (SEM) and chemical composition by Energy Dispersive X-ray Spectroscopy (EDS). The hardness of MgO and MgO:B5H10NaO13 doped composite oxide coatings were determined by microhardness tester, the adhesion resistance with the base material was determined by Scratch Tester and the corrosion resistance was determined by potentiodynamic polarization tester. As a result, it was observed that dense and homogeneous coatings were grown on the surfaces of particle-added (MgO:B5H10NaO13) coatings, that porosity and pore sizes on the surfaces of the coatings were reduced, that microcracks were reduced, and that coatings with high bond strength with the base material were grown. It was also determined that the corrosion resistance of the coatings with particle addition (MgO:B5H10NaO13) was higher than the corrosion resistance of the coatings without particle addition (MgO).

  • MakaleAçık Erişim2025
    Corrosion and structural properties of lightweight magnesium and aluminum alloy cores based sandwich composites

    Keleş, Abdulsamet; Karabudak, Filiz; Acar, Volkan; Kula, M. Emin; Aslan, Mustafa; Karabacak, A. Hasan; Alibeyoğlu, Fatih

    Metal plate core-based sandwich composites have the potential to revolutionize various industrial fields due to their mechanical strength and vibration damping. In this study, AZ91 (a magnesium alloy) and Al1050 (an aluminum alloy) metal core-based sandwich composites of AZ91/carbon fiber-epoxy, AZ91/glass fiber-epoxy, Al1050/carbon fiber-epoxy, and Al1050/glass fiber-epoxy sandwich composites were manufactured. These composites' mechanical and dynamic properties were determined through tensile, three-point bending, and vibration tests. AZ91-reinforced carbon fiber composites exhibited a 28.8% higher tensile strength than glass fiber composites, while Al1050-reinforced carbon fiber composites showed a 17.2% higher tensile strength performance than glass fiber composites. Moreover, AZ91 reinforcement led to composites with higher average flexural strength for both fibers. In vibration tests conducted under clamped and free-free boundary conditions, the highest first natural frequency was observed in AZ91/carbon fiber samples, sparking further interest. Conversely, the highest first damping ratio was observed in Al1050/glass fiber specimens. In addition, the corrosion behavior of sandwiches was evaluated, and it was found that glass fiber provided better corrosion resistance than carbon fiber. Highlights: Sandwich composites comprising AZ91/Al1050 cores and carbon/glass fiber reinforced epoxy face sheets were manufactured. Galvanic corrosion effects were evaluated, and glass fiber was found to provide higher corrosion resistance. AZ91/carbon fiber sandwich showed 28.8% higher tensile strength than glass fiber. Vibration tests revealed the AZ91/carbon fiber sandwich had the highest first natural frequency. Al1050/glass fiber sandwich exhibited the highest first damping ratio.

  • MakaleYalnız künye2025
    Characterization, corrosion, adhesion and wear properties of Al2O3 and Al2O3:TiB2 composite coating on Al 7075 aluminum alloy by one-step micro-arc oxidation method

    Sukuroglu, Suleyman

    This study was carried out in order to increase the usage areas of Al 7075 alloy, which is preferred as an engineering material in the aerospace industry, defense industry and automotive industry, in high temperature applications, wear resistance in different environments and corrosion resistance in aggressive environments. For this purpose, the focus was on the growth of Al2O3 and Al2O3:TiB2 doped composite coatings on the surface of Al 7075 aluminum alloy by the MAO method, and the structural, morphological, corrosion, adhesion and wear properties of the grown coatings in three different environments (atmospheric conditions, brine containing 3.5 % NaCl and oil). Firstly, Al2O3 coatings were grown in electrolytic solution number 1. Secandly, Al2O3:TiB2 doped composite coatings were grown in electrolytic solution number 2 and the phase structure, microstructure and chemical composition of the grown coatings were determined by X-ray Diffraction, Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, respectively. The abrasion behavior of the coatings in three different environments was determined by a pin-on disc abrasion tester, adhesion resistances were determined by a Scratch Test, and corrosion resistance was determined by a potentiodynamic polarization tester. It was observed that dense and uniform coatings were grown on the surfaces of TiB2 nanoparticle-added (Al2O3:TiB2) coatings, porosity and pore sizes on the surfaces of the coatings were reduced and microcracks were reduced. In addition, it was determined that the corrosion resistance and wear resistance of composite coatings (Al2O3:TiB2) grown with nanoparticle addition increased, and coatings with high bond strength with the substrate were grown.

  • MakaleAçık Erişim2021
    Wear, Corrosion and Tribocorrosion Behavior of Polyurethane and Polyvinylpyrrolidone Blends as Coating for Corrosion Protection of AISI 316L Stainless Steel

    Taşdemir, Muharrem; Şenaslan, Fatih; Çelik, Ayhan

    Polyurethanes (PUs) are used across a widely from biomaterials to industrial applications due to their versatile properties. Polyurethane is blended with other polymers to improve their physical and thermal properties. In this study, different concentrations of polyurethane and polyvinylpyrrolidone (PVP) blends were applied to AISI 316L stainless steel using the dip coating method as protection against wear and corrosion. The effects of different concentrations of blends on the mechanical, corrosion and tribocorrosion properties of the AISI 316L stainless steel were investigated. The phase structure of polymer coatings were investigated by X-ray diffraction (XRD), and their surfaces were examined by scanning electron microscopy (SEM). Corrosion and tribocorrosion tests of the polymer coated samples were carried out in 3.5% NaCl solutions. The surface roughness and nanohardness of the polymeric coated samples were also measured. It was found that surface roughness and friction coefficient increased with raised concentration of PVP, while wear and corrosion resistance decreased with the increased of PVP concentration in the coating. As the penetration depth of the PU coated sample increased, the nanohardness and elasticity modulus decreased. Coatings containing PVP up to 25% protected the substrate surface under tribocorrosion conditions in NaCl solutions.

  • MakaleYalnız künye2016
    Influence of CrN Coating on Electrochemical Behavior of Plasma Nitrided Pure Titanium in Bio-simulated Environment

    Çelik, Ilhan

    Titanium and its alloys are widely used as materials for bio-medical applications, such as implants. However, ions of the alloy can release to the body region and spread into the blood circulation. In this study, plasma nitriding and CrN coating techniques are used in order to overcome the problem of ion release. The objective of this study was to investigate the effects of plasma nitrided pure titanium on the structural properties and corrosion behaviors before and after CrN coating in Ringer's solution at 37 °C. The structural properties were investigated using Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). A diffusion layer and a compound layer composed of δ-TiN and ε-Ti2N phases were observed on the surface of nitrided pure titanium. Corrosion tests were made for the determination of electrochemical properties with the help of Potentiostat/Galvanostat device. The results show that corrosion behaviors of untreated and treated samples have similar characteristic.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
  • MakaleYalnız künye2016
    Effect of plasma nitriding treatment on structural, tribological and electrochemical properties of commercially pure titanium

    Çelik, Ilhan; Karakan, Mehmet

    In this study, plasma nitriding treatment was applied to commercially pure titanium (Grade 2). Structural properties, electrochemical and tribological behaviours of the nitrided pure titanium specimens were comparatively investigated. Microstructure and morphology of the plasma nitrided specimens were analysed by X-ray diffraction and scanning electron microscopy. Furthermore, corrosion tests were conducted in Ringer's solution, which represents a human body environment, to determine electrochemical properties. Then, tribological and frictional properties were investigated using pin-on-disc tribometer, and a micro-hardness tester was used to measure the hardness of the coatings. The results showed that plasma nitrided specimens exhibited higher surface hardness than the untreated specimens did. In addition, the plasma nitrided specimens at 700 °C presented significantly better performance than the other plasma nitrided specimens (at 500 °C and 600 °C) under dry wear conditions. Moreover, corrosion test results showed that corrosion behaviours of untreated and nitrided samples had similar characteristic.