Kurum Yazarı "Ayas, Erhan" Scopus İndeksli Yayınlar Koleksiyonu İçin Listeleme
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An alternative composite approach to tailor the thermoelectric performance in SiAlON and SiC
Kaya, Pınar; Gregori, Giuliano; Yordanov, Petar; Ayas, Erhan; Habermeier, Hanns-Ulrich; Maier, Joachim; Turan, Servet (Elsevier Sci LTD, 2017)The thermoelectric properties of SiAlON and SiC based composites prepared by adding TiCN (5 and 10 vol.%) as a particulate or as a segregated three-dimensional network were investigated. Although the volume fraction of the ... -
Analytical transmission electron microscopy observations on the stability of TiCN in electrically conductive alpha-beta SiAlON/TiCN composites
Yurdakul, Hilmi; Turan, Servet; Ayas, Erhan; Tunckan, Orkun; Kara, Alpagut (Elsevier Sci LTD, 2014)Coating of alpha-beta SiAlON granules with TiCN powder led to a continuous 3D electrically conductive network formation. Here, the stability of TiCN grains following gas pressure sintering (GPS) and its effect on the ... -
Decolouration effect of WC addition on gas pressure sintered alpha-beta SiAlON ceramics
Ayas, Erhan; Kara, Alpagut; Mandal, Hasan; Turan, Servet; Kara, Ferhat (Elsevier Science BV, 2004)In this study, an attempt was made to mask an inhomogeneous gray colouration featured on the surfaces of the gas pressure sintered alpha-beta SiAlON ceramics containing 50% alpha and 50% beta SiAlONs in the form of spots. ... -
Densification and properties of in-situ synthesized ZrB2-SiC composities from ZrO2, B4C and SiC system
Gürcan, Kübra; Yılmaz, Burcu; Ayas, Erhan (Korean Assoc Crystal Growth, Inc, 2017)Zirconium diboride-silicon carbide (ZrB2-SiC) ceramics were in-situ synthesized and densified by the spark plasma sintering (SPS) method using ZrO2, B4C and SiC as starting powders. Both synthesis and densification processes ... -
The effect of heat-treated boron derivative waste at 600 degrees C on the mechanical and microstructural properties of cement mortar
Kaman, Derya Over; Köroğlu, Levent; Ayas, Erhan; Güney, Yücel (Elsevier Sci LTD, 2017)Turkey holds 73% of the world's boron deposits. 25.3% of the total deposits are tincal ore and located in Eskisehir Kirka region. During the production of 1 million tons of borax pentahydrate (Na2O center dot 2B(2)O(3)center ... -
Effect of Precipitation Method on Properties of Hydroxyapatite Powders
Yoruc, A. B. Hazar; Karakaş, A.; Ayas, Erhan; Koyun, A. (Polish Acad Sciences Inst Physics, 2013)The aim of this study was the compare the properties of hydroxyapatite as a function of two different methods (chemical and biomimetic precipitation). Powder products were called as chemical hydroxyapatite for chemical ... -
Fabrication and microstructural stability of spark plasma sintered Al2O3/Er3Al5O12 eutectic
Özerdem, Ece; Ayas, Erhan (Elsevier Sci LTD, 2015)Al2O3-Er3Al5O12 (BAG) eutectic was prepared by a arc melting process under Ar atmosphere. Button shaped melts, containing fine sized irregular eutectic structures of 'Chinese script', with interpenetrated Al2O3 and EAG ... -
Fabrication of in situ Ni(W)-WC nano composites via mechanical alloying and spark plasma sintering
Genç, A.; Ayas, Erhan; Öveçoğlu, M. L.; Turan, Servet. (2012)Microstructural and mechanical properties of spark plasma sintered Ni-30 wt% W powders fabricated via mechanical alloying (MA) for 48 h were reported in the present study. Due to the intensive WC contamination during MA, ... -
In vitro cytotoxicity of monticellite based bioactive ceramic powder synthesized from boron derivative waste
Barutca, Banu; Köroğlu, Levent; Ayas, Erhan; Koparal, Ayşe Tansu (Elsevier Sci LTD, 2018)The cytotoxicity of monticellite based bioactive ceramic powder, which was synthesized from boron derivative waste has been determined by in vitro assays of MTT, NRU, and JC-1 staining. The toxicity of powder on different ... -
In-situ synthesis and densification of HfB2 ceramics by the spark plasma sintering technique
Gürcan, Kara; Ayas, Erhan (Elsevier Sci LTD, 2017)Hafnium diboride (HfB2) ceramics were in-situ synthesized and densified by the spark plasma sintering (SPS) method using HfO2 and amorphous boron (B) as starting powders. Both synthesis and densification processes were ... -
Magnetic MCM-41 silica particles grafted with poly(glycidylmethacrylate) brush: Modification and application for removal of direct dyes
Arıca, Tugce A.; Ayas, Erhan; Arıca, M. Yakup (Elsevier Science BV, 2017)Magnetic MCM-41composite particles were prepared and modified with (3-aminopropyl) triethoxysilane (APTES), then grafted with poly(glycidyl methacrylate) p(GMA) by surface-initiated atom transfer radical polymerization ... -
Mechanical Properties of Cement Mortar Containing Heat-Treated Boron Derivative Waste at Elevated Temperatures
Kaman, Derya Over; Köroğlu, Levent; Ayas, Erhan; Tokyay, Mustafa; Güney, Yücel (Asce-Amer Soc Civil Engineers, 2018)The largest boron reserves in the world are located in Turkey. The production of boron compounds and use of generated boron derivative waste during this production are extremely important for both economically and ... -
Microstructural evolution of mechanically alloyed and spark plasma sintered Ni-W alloy matrix composites
Genç, A.; Kaya, P.; Ayas, Erhan; Öveçoğlu, M. L.; Turan, Servet. (2013)Microstructural evolution of Ni(W) solid solution alloys fabricated via mechanical alloying (MA) of Ni - 30 wt.% W powders and spark plasma sintering (SPS) at 1000 C for 3 min were presented in this study. Due to contaminations ... -
A novel approach for preparing electrically conductive alpha/beta SiAlON-TiN composites by spark plasma sintering
Ayas, Erhan; Kara, Alpagut; Kara, Ferhat (Ceramic Soc Japan-Nippon Seramikkusu Kyokai, 2008)An effective approach for preparing electrically conductive SiAlON-TiN composites have been developed. Granules of a designed composition of alpha-beta SiAlON were obtained by spray drying and coated with varying amounts ... -
A Novel Approach For Preparing Electrically Conductive SiAlON-TiN Composites by Spark Plasma Sintering
Ayas, Erhan; Kara, Alpagut; Kara, Ferhat (Trans Tech Publications LTD, 2009)An effective approach for preparing electrically conductive SiAlON-TiN composites was developed. Granules of a designed composition of alpha-beta SiAlON was obtained by spray drying and coated with varying amounts of TiO(2) ... -
A novel approach for synthesis of monticellite based bioactive ceramic powders from boron derivative waste
Köroğlu, Levent; Butev, Ezgi; Esen, Ziya; Ayas, Erhan (Elsevier Science BV, 2017)Monticellite bioactive ceramics have a high usage potential as bone graft substitutes due to their superior mechanical properties compared to hydroxyapatite and excellent bioactivity. Turkey has almost 72% of the global ... -
Novel electrically conductive alpha-beta SiAlON/TiCN composites
Ayas, Erhan; Kara, Alpagut (Elsevier Sci LTD, 2011)Electrically conductive alpha-beta SiAlON/TiCN composites were produced in the form of a segregated network in a ceramic matrix structure. A continuous 3D network of conductive TiCN particles was successfully achieved by ... -
Optimization of the optical properties of alpha-SiAlON through a decrease in starting powder size
Kurama, Semra; Avcıoğlu, Suna; Ayas, Erhan (Elsevier Sci LTD, 2015)In the present work, the effects of initial powder size on the sintering behavior and optical properties of Dy-alpha-SiAlON ceramics produced by the SPS technique are investigated. The powders were prepared using high ... -
Oxidation behavior of electrically conductive alpha/beta SiAlON composites with segregated network of TiCN
Çelik, Ali; Ayas, Erhan; Halil, Etem; Kara, Alpagut (Elsevier Sci LTD, 2012)The oxidation behavior of novel electrically conductive alpha/beta SiAlON composites with a continuous network of 2.5-10 vol% TiCN particulates was investigated. Composites, produced by coating spray dried granules with ... -
Pressureless sintering of Al2O3-TiCN composites
Ayas, Erhan; Kara, Alpagut (Trans Tech Publications LTD, 2004)A composition of 70 wt % Al2O3 + 30 wt % TiCN was prepared and pressureless-sintered at temperatures ranging from 1700 to 1840degreesC. In order to achieve densification, a powder bed was also employed. The resultant ...