Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
Browse
3 results
Search Results
Conference Object Citation - WoS: 8Citation - Scopus: 12Mechanical Properties of Hydroxyapatite Composites Reinforced With Hydroxyapatite Whiskers(Trans Tech Publications, 2004) Şimşek, Deniz; Çiftçioğlu, Rukiye; Güden, Mustafa; Çiftçioğlu, Muhsin; Harsa, Hayriye ŞebnemSintering and mechanical behavior of pure and hydroxyapatite (HA) whisker reinforced HA composites were investigated in this work. Pure and composite samples were prepared by using a commercial powder and whiskers prepared by molten salt synthesis. The dry-pressed samples were sintered in the 800 and 1300°C range. The effect of whisker-addition on the mechanical properties of HA was investigated through compression and hardness testing. Compressive strength and fracture strain were observed to increase by the addition of whiskers.Article Citation - WoS: 54Citation - Scopus: 62Sic-Particulate Aluminum Composite Foams Produced by Powder Compacts: Foaming and Compression Behavior(Springer Verlag, 2003) Elbir, Semih; Yılmaz, Selahattin; Toksoy, Ahmet Kaan; Güden, Mustafa; Hall, Ian W.The foaming behavior of SiC-particulate (8.6% by volume) aluminum composite powder compacts contained Titanium Hydride blowing agent was investigated by heating above the melting temperature (750°C) in a pre-heated furnace. Aluminum powder compacts were also prepared and foamed using similar compaction and foaming parameters in order to determine the effect of SiC-particulate addition on foaming and compression behavior. The linear expansions of the compacts at various furnace holding times were ex situ determined. Optical and scanning electron microscopy techniques were used to characterize prepared and deformed foams microstructures. The SiC-particulate addition was found to increase the linear expansion and reduce the extent of the liquid metal drainage and cell coarsening of the aluminum compacts. The composite foam samples also showed higher compressive stresses, but a more brittle behavior as compared with aluminum foams.Conference Object Citation - WoS: 5Citation - Scopus: 5Preparation and Microstuructural Development of Nanocrystalline Titania and Alumina(Trans Tech Publications, 2004) Çağlar Duvarcı, Özlem; Çiftçioğlu, Muhsin; Güden, Mustafa; Arıkut, G.The preparation of nanocrystalline titania and alumina was investigated by sol-gel methods using titanium isopropoxide, boehmite and aluminum isopropoxide. Various drying control chemical additives like oxalic acid, acetic acid and polyacrylic acid were used for modifying the drying behaviour and shrinkage of the gels. The sintered densities of the ceramics prepared by sol-gel processing and the dried gels were in the 79-99% of theoretical density for rutile. The green and sintered densities of the pellets prepared by uniaxial pressing of powders derived from sols, gels and precipitation techniques for titania were in the 40-52% and 55-83% respectively. The titania ceramics were observed to experience anatase-rutile phase transformation upon heat treatment at 650oC. The grain size of the sintered ceramics at 650oC was determined to be about 26 nm. Grain size of titania increased to 213 nm. at 850oC. The mechanical properties of these nanocrystalline ceramics were investigated by using microhardness testing.