Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Now showing 1 - 4 of 4
  • Article
    Citation - WoS: 3
    Citation - Scopus: 2
    Electrocaloric Behaviour of Tape Cast and Grain Oriented Nbt-Kbt Ceramics
    (Elsevier Sci Ltd, 2024) Unal, Muhammet Ali; Karakaya, Merve; Irmak, Tugce; Yildirim-Ozarslan, Gokce; Avci, A. Murat; Fulanovic, Lovro; Adem, Umut
    We have investigated the effects of grain orientation and tape casting process on the electrocaloric properties of 0.82Na(0.5)Bi(0.5)TiO(3)-0.18 K0.5Bi0.5TiO3 (0.82NBT-0.18KBT) ceramics at the Morphotropic Phase Boundary (MPB), using direct and indirect measurements. We observe a larger electrocaloric response for the template-free ceramics compared to 7 and 10 wt% template containing ones, suggesting that grain orientation along rhombohedral < 100 > does not improve the electrocaloric response. Indirect measurements yielded a large adiabatic temperature change of around 3 K under an electric field of 50 kV/cm, which is significantly higher than 0.9 K reached at a lower electric field of 40 kV/cm using the direct measurement.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 17
    Biocompatibility of Silicon Nitride Produced Via Partial Sintering & Tape Casting
    (Elsevier Ltd., 2021) Çeçen, Berivan; Topateş, Gülsüm; Kara, Aylin; Akbulut, Serdar Onat; Havıtçıoğlu, Hasan; Kozacı, Leyla Didem
    The biocompatibility of silicon nitride ceramics was proven by several studies however this study is apart from the literature in the manner of production routes that are tape casting and partial sintering. We report the tape casting route was chosen and a porous structure was obtained by partial sintering technique. Tape casting brought a smooth surface to the samples. Density and pore size distribution analysis showed that the scaffolds have low density because of the porous structure. XRD and SEM analyses were carried out to reveal the phase and microstructural characteristics of porous ceramic samples. Static contact angle measurement was done for the characterization of the wettability of the scaffolds. It revealed that the surface of the scaffolds was highly hydrophilic which is a desirable characteristic for the protein and cell adhesion. The mechanical characteristics of the scaffolds were analyzed by compression tests. Human osteosarcoma cells were used for in vitro studies. Cell-proliferation and cytotoxicity were analyzed by WST-1 and LDH, respectively. The osteoblastic behavior of the cells on the surface of the scaffolds was identified by alkaline phosphatase activity. BCA analysis was used for total protein content. The BCA and ALP results showed an increasing trend which is directly correlated with cell proliferation. Cells on the surface of the silicon nitride scaffolds were visualized by SEM and fluorescence microscopy where the images supported the in vitro analysis. Therefore, porous silicon nitride scaffolds fabricated via tape casting and partial sintering were biocompatible and they are possible candidates as bone substitute elements. © 2020 Elsevier Ltd and Techna Group S.r.l.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 9
    Preparation of the Pb(mg1/3nb2 Films by Aqueous Tape Casting
    (Elsevier Ltd., 2009) Şakar-Deliormanlı, Aylin; Çelik, Erdal; Polat, Mehmet
    Lead magnesium niobate (PMN) is a relaxor ferroelectric material. Because of its high dielectric constant and superior electrostrictive properties it is commonly used in the manufacture of multilayer electronic devices which is typically produced by tape casting. However, preparation of PMN slurry formulations to use in aqueous tape casting process is not investigated in detail yet. Therefore, in this study aqueous PMN formulations were developed for tape casting and its relation with the final properties of PMN films were investigated. The slurries were prepared using poly(acrylic acid)-based comb polymer as the dispersant, nonionic acrylic latex as the binder and the hydroxypropyl methyl cellulose as the wetting agent. The results showed that it is possible to prepare flexible, crack-free PMN films using highly concentrated suspensions without using any plasticizer. The study gives guidelines for the aqueous tape casting of PMN and can be adapted to processing of other multi-component metal oxides.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 6
    Thermal Analysis and Microstructural Characterization of Ceramic Green Tapes Prepared by Aqueous Tape Casting
    (Springer Verlag, 2008) Şakar-Deliormanlı, Aylin; Çelik, Erdal; Polat, Mehmet
    In this study, aqueous lead magnesium niobate (PMN) slurry formulations were developed for tape casting using a poly(acrylic acid) - poly(ethylene) oxide comb polymer as the dispersant, nonionic acrylic latex as the binder phase and hydroxypropyl methylcellulose as the wetting agent. Concentrated suspensions were cast onto a silicone-coated mylar film, and the effect of acrylic latex on deposition was investigated. Thermal analyses were performed to investigate the mass loss of the green tapes as a function of calcination temperature. Differential scanning calorimetric analyses were made under air and nitrogen atmospheres to investigate the binder distribution through the green tapes. Results showed that it is possible to prepare flexible, crack free PMN thick films using a proper slurry composition in the presence of acrylic latex binder, without using any plasticizer. Additionally, decomposing mechanisms of the acrylic based binder were essentially different in the two atmospheres.