Yazar "Akderya, Tarkan" seçeneğine göre listele

Listeleniyor 1 - 6 / 6
  • Küçük Resim
    Öğe
    Effects of post-uv-curing on the flexural and absorptive behaviour of fdm-3d-printed poly(lactic acid) parts
    (Mdpi, 2023) Akderya, Tarkan
    In this study, the effects of the post-ultraviolet-curing process on the flexural, absorptive, and morphological properties of poly(lactic acid) specimens produced using a fused deposition modelling technique 3D printer were experimentally investigated. In this direction, 15, 30, 45, and 60 min post-UV-curing processes were applied to poly(lactic acid) three-point bending and absorption specimens produced at 190 and 200 degrees C. Three-point bending tests and morphological analyses were applied after the post-ultraviolet-curing process, and absorption tests were applied by immersing the post-ultraviolet-cured specimens in a distilled water bath for 1-, 3-day, and 1-, 2-, and 4-week exposure times. The changes in flexural strain properties for each experimental parameter were also simulated by the computer-aided finite element analysis and compared with the experimental results. It was observed that the post-ultraviolet-curing process increased the flexural strength of the poly(lactic acid) specimens produced at both 190 and 200 degrees C with the same increasing trend up to 30 min of exposure, and the most significant increase was determined in the specimens that were subjected to post-ultraviolet-curing for 30 min. Although the flexural strengths of the post-ultraviolet-cured specimens were higher than the non-cured specimens in all conditions, it was detected that they tended to decrease after 30 min.
  • Küçük Resim Yok
    Öğe
    Green Campus Certification and Sustainability Relations: Case of İzmir Bakircay University
    (Tuba-Turkish Acad Sciences, 2024) Kose, Bayram; Ansay, Serkan; Akderya, Tarkan; Tabakoglu, Guelbahar; Hiziroglu, Abduelkadir; Berktas, Mustafa
    Technological advances, population growth and diversifying consumption habits are putting increasing pressure on natural resources, while preserving the ecological balance and protecting the rights of all living beings is of critical importance. The fair and sustainable use of resources is indispensable to ensure environmental sustainability. In this context, the United Nations' initiatives to combat climate change and the European Green Deal guide sustainability efforts based on the harmony of human life and ecosystems. In this study, green campus certification processes carried out by universities with a free and scientific approach and their connection with sustainable development goals are discussed. In addition, the green certification efforts of universities in Turkey have been examined in detail and the reflections of these efforts across the country have been evaluated. The findings reveal that universities in Turkey have increasingly prioritized sustainability efforts in recent years and have expanded their position among green-certified institutions by increasing their level of awareness.
  • Küçük Resim
    Öğe
    Investigation of long-term ageing effect on the thermal properties of chicken feather fibre/poly(lactic acid) biocomposites
    (Springer, 2020) Akderya, Tarkan; Özmen, Uğur; Baba, Buket Okutan
    In this study, the effects of long-term natural atmospheric ageing on the thermal properties of chicken feather fibre reinforced poly(lactic acid) biocomposite materials having chicken feather fibre mass content of 2, 5, and 10% were investigated. Chicken feather fibres, which are bio-based reinforcement material, and poly(lactic acid), which is bio-based matrix material, are compounded with a twin-screw extruder and injection-moulded; hence, the biocomposite material is produced. The effect of long-term natural atmospheric ageing on the thermal stability, crystallization, and melting behaviour of the biocomposite materials were analysed by thermogravimetric, derivative thermogravimetry, differential thermal, and differential scanning calorimetry analyses. In addition, the fracture surface of the samples was examined in depth by scanning electron microscopy analysis. The experimental results show that the long-term natural ageing process decreases the thermal stability values of the biocomposite materials and increases the glass transition temperatures and degree of crystallinities.
  • Küçük Resim Yok
    Öğe
    A micromechanical approach to elastic modulus of long-term aged chicken feather fibre/poly(lactic acid) biocomposites
    (Walter De Gruyter Gmbh, 2022) Akderya, Tarkan; Özmen, Uğur; Baba, Buket Okutan
    The modulus of elasticity is a critical parameter for the performance design and analysis of biofibre-based biocomposite materials. As a result of criteria such as internal heterogeneity, the random distribution of fibres and the success of interfacial adhesion between the fibre and the matrix, it becomes difficult to predict the modulus of elasticity in practical ways. Therefore, one of the aims of this study is to determine the modulus of elasticity of biocomposite material reinforced with discontinuous and random fibres by means of micromechanical models and experimentally. In addition, it is also aimed to reveal which micromechanical model can be used reliably in predicting the modulus of elasticity of both aged and non-aged biocomposite materials due to the relationship between the analytical and experimental results. In order to achieve these objectives, initially, chicken feather fibre/poly (lactic acid) biocomposite specimens having 2, 5 and 10 % chicken feather fibre mass fractions were mixed and manufactured by extruding, and subsequently, tensile test specimens according to the appropriate standard were formed by the injection-moulding method. An agreement between the moduli of elasticity obtained from 6 micromechanical models and experimentally from the slope of the stress-strain curves resulting from tensile tests was determined.
  • Küçük Resim
    Öğe
    Revealing the long-term ageing effect on the mechanical properties of chicken feather fibre/poly(lactic acid) biocomposites
    (Korean Fiber Soc, 2021) Akderya, Tarkan; Özmen, Uğur; Baba, Buket Okutan
    Recently, bio-based polymer composites have been preferred instead of petroleum-based polymer composites due to increased sensitivity, awareness, and interest level in the fields of depletion of oil resources and environmental pollution. These eco-friendly materials, also called green composites, are reinforced with natural fibres and have superior properties such as biodegradability. In this paper, the effect of long-term ageing on mechanical properties of biocomposite material containing chicken feather fibre (CFF) as additive and poly(lactic acid) (PLA) as matrix is studied. The mechanical properties of pure PLA and CFF/PLA biocomposites, which are gradually increasing in mass concentrations of 2 %, 5 % and 10 %, have been investigated by tensile, compressive and hardness tests, and also the fracture surfaces were examined by SEM micrographs. The experimental results show that the long-term ageing effect causes the mechanical properties of pure PLA and CFF/PLA biocomposites to decrease. The lowest values of mechanical properties are found in the 5 % and 10 % CFF/PLA biocomposite materials that have the highest mass concentration of CFF.
  • Küçük Resim Yok
    Öğe
    The Influence of Printing Speed and Temperature on the Mechanical, Absorptive, and Morphological Properties of PLA-Based Hybrid Materials Produced with an FDM-Type 3D Printer
    (Multidisciplinary Digital Publishing Institute (MDPI), 2024) İncesu, Rumeysa; Akderya, Tarkan
    Composite materials are used in many engineering applications and industrial fields due to their superior properties, such as high strength, lightweight, and stiffness. These outstanding properties have made these materials an alternative to metallic materials. The vital need for new lightweight and inexpensive materials with superior strength properties has led to research on “hybridisation”. Hybrid composites with more than one type of polymer in the same structure are needed to achieve a better balance of properties and to combine many desired properties in a single material. Many researchers have studied the hybrid effect and contributed to the understanding and modelling of the subject. Studies to explain the primary mechanism of the hybrid effect are limited and insufficient to explain the complex interaction. In this study, a three-dimensional printer using fused deposition modelling technique was used to produce hybrid materials, and the influence of printing parameters on the mechanical, absorptive, and morphological properties of poly (lactic acid) (PLA), Tough PLA, and PLA/Tough PLA hybrid materials were investigated. The hybrid material form exhibited superior properties when selecting specific production parameters from individual raw elements. It can be said that the mechanical properties of the PLA/Tough PLA hybrid material increased with the increase in production temperature. © 2024 by the authors.