Malzeme Bilimi ve Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/396
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Article Citation - WoS: 9Citation - Scopus: 11Boriding Kinetics and Mechanical Properties of Borided Commercial-Purity Nickel(Natl inst Science Communication-niscair, 2017) Uçar, Nuri; Calik, A.; Ucar, N.; Delikanli, K.; Carkci, M.; Karakas, S.; Bankacılık ve FinansKinetics of boride layer growth and tensile behaviour in bonded commercial-purity nickel was investigated. Bonding was carried out in a solid medium consisting of Ekabor-II powders at 1173, 1223 and 1273 K for periods of 3, 5 and 8 h. Scanning electron microscopy (SEM) and optical microscopy showed column morphology in the boride layer. X-ray diffraction (XRD) analyses indicated that the boride layer formed on the surface consisted mainly of Ni2B, with precipitates of Ni6Si2B. A parabolic relationship between layer thickness and processing temperature was observed. The obtained results showed that although the boride layer thickness increased with increasing boriding temperature and time, boriding parameters had no significant effect on the hardness of the boride layer or the matrix. Tensile properties were negatively influenced by the bonding treatment; both yield and tensile strength values decreased due to the presence of the hard yet brittle surface coating. In addition, the growth kinetics of boride layers was also analysed. The results showed a nearly parabolic relationship between the layer thickness and the process temperature, with activation energy of 47.3 kJ mol(-1).Article Citation - WoS: 2Citation - Scopus: 2Coating of Si3n4 With Hap Via Atomic Layer Deposition(Korean Assoc Crystal Growth, inc, 2023) Akin, Seniz R. KushanSilicon nitride (Si3N4) is an attractive implant material, particularly in orthopedic surgery. Although it has only been on the market for spinal fusion surgery requirements so far, it is also a promising candidate for other implant applications where load-bearing is crucial. In this study, we aimed to examine the potential of making the material surface more advantageous for various implant applications by coating it with a very thin hydroxyapatite (HAp) layer using the atomic layer deposition (ALD) method. This was done to improve the material's bioactivity without sacrificing its mechanical properties. Characterization results showed that using a 3:1 CaO:PO4 ALD cycle ratio resulted in the formation of very fine crystalline HAp after heat treatment at 500 degrees C. The bioactivity assessment made by immersing the coated film in SBF revealed HAp formation on the surface, and it was observed that the bioactivity of this surface improved compared to the uncoated one.Article Synthesis, Molecular Structure and Dft Study of 2-(n Benzoate(Springer/plenum Publishers, 2011) Kazak, Canan; Ozdogan, Cem; Guvenc, Ziya B.; Buyukgungor, Orhan; Arslan, Figen; Odabasoglu, Mustafa; Yuksektepe, CigdemThe biologically important 2-amino-3-hydroxypyridine reacts with benzoyl chloride to give 2-(N-benzoylbenzamido)pyridine-3-yl benzoate. This synthesized compound has been studied by elemental analysis, X-ray crystallography and also theoretically by density functional theory (DFT) framework with B3LYP/6-311++G(d, p) level of theory. The molecules of this compound crystallize in the orthorhombic space group of P2(1)2(1)2(1) and the crystal packing involves both hydrogen-bonding and C-Ha <-pi interaction. The vibrational normal modes of the molecular structure are investigated by ab initio method for both infrared intensities (IR) and for Raman activities. Furthermore, the corresponding assignments are discussed. Hydrogen and carbon atoms of the benzene rings are found to be highly active. Also, experimentally obtained IR spectrum is presented and compared with the available theoretical data. Experimentally and theoretically obtained IR spectrum are in good agreement.