Güncel Gönderiler: Fen Bilimleri Enstitüsü
Toplam kayıt 2521, listelenen: 141-160
-
Preparation of multiple-cation alpha-SiAlON ceramics containing lanthanum
(Amer Ceramic Soc, 1999)Until recently, it was accepted that Ce3+ cations, with an ionic radius (r) of 1.03 Angstrom, were too large to form an alpha-SiAlON structure. However, more-recent studies have shown that cerium cations can be incorporated ... -
Wetting and non-wetting behaviour of silicon carbide grain boundaries
(Transtec Publications LTD, 1999)Silicon carbide (SiC) grain boundaries have been observed to be free from intergranular films. On the basis of equilibrium film thickness calculations, it has been proposed elsewhere that because SiC has very high refractive ... -
Capacitor discharge joining of silicon carbide based ceramics
(Trans Tech Publications LTD, 2002)A capacitor-discharge joining technique has been successfully used to join oxide ceramics using thin metal foils. In this study, silicon carbide (SiC) ceramic joints and silicon carbide-titanium diboride (TiB2) composite ... -
Orientation-dependent equilibrium film thickness at interphase boundaries in ceramic-ceramic composites
(IOP Publishing LTD, 1997)Theoretical considerations of the Hamaker constant for the interaction of two media across a third suggest that the highly anisotropic nature of the refractive indices of a medium such as h-BN will produce an orientation ... -
The crystallography of interphase boundaries between silicon carbide and silicon nitride in silicon nitride - Silicon carbide particulate composites
(Kluwer Academic Publ, 2000)Interphase boundaries between 3C SiC grains and two different beta-Si3N4 morphologies in Si3N4-SiC composites have been studied by transmission electron microscopy. In general, boundaries between small beta-Si3N4 intragranular ... -
Solid-state ceramic actuator designs
(Amer Inst Aeronaut Astronaut, 2001)Smart electromeehanical systems consist mainly of sensors, actuators, and data processing units. Actuators are the responding units of many smart systems including those for active vibration control and noise control. ... -
Microstructural characterization of reactively sintered mullites
(Amer Ceramic Soc, 2000)Mullite ceramics have been produced by reaction sintering of powders prepared using pseudoboehmite-colloidal silica and aluminum sulfate-colloidal silica mixtures. The microstructural development of these mullites was ... -
Capacitor-discharge joining of oxide ceramics
(Amer Ceramic Soc, 1999)A capacitor-discharge joining technique has been used to fabricate alumina-metal-alumina and zirconia-metal-zirconia joints using thin foils of aluminum, titanium, or amorphous AlxNiyYz alloys as interlayers. The technique ... -
Cyclic crack growth behaviour of two nickel base turbine disc alloys
(Kluwer Academic Publ, 1998)The high temperature fatigue crack growth behaviour of the nickel base superalloys Alloy 718 and Rene 95 (specimen thickness = 4.1 mm) were investigated and compared with each other. Fatigue crack propagation (FCP) tests ... -
Improvement of elongated alpha-SiAlON ceramics by variation of the processing conditions and amounts of additives
(Trans Tech Publications LTD, 2002)Two types of Y-alpha -SiAlON composition, with different amounts of additional liquid phase were densified in a gas pressure sintering furnace using three different sintering cycles. One series of samples was heated up to ... -
Hydrothermal synthesis of tabular perovskite particles
(Trans Tech Publications LTD, 2002)Phase pure perovskite lead titanate and lead zirconate titanate powders were produced by hydrothermal synthesis. Reaction temperature and time are critical processing parameters for formation of phase-pure perovskite ... -
Textured alumina ceramics by uniaxial pressing
(Trans Tech Publications LTD, 2002)Highly textured, dense alumina ceramics were fabricated by a processing route which utilizes a mixture of Al metal powder, alumina powder, alumina platelet (template) particles and a liquid phase former. The process involves ... -
Structural analysis of bio-oils from fixed-bed pyrolysis of Euphorbia rigida and sunflower pressed bagasse
(Taylor & Francis Inc, 2000)Fixed-bed tars of Euphorbia rigida and sunflower pressed bagasse have been investigated for their structures. These mrs were fractionated into pentane-soluble and -insoluble compounds (asphaltenes). Pentane soluble were ... -
The effect of processing conditions, amount of additives and composition on the microstructures and mechanical properties of alpha-SiAlON ceramics
(Elsevier Sci LTD, 2002)A series of samples with yttrium alpha -SiAlON compositions and different amounts of additive has been fabricated from alpha -Si3N4, AIN, Al2O3 and Y2O3 starting powders, using gas pressure sintering and three different ... -
The design of compositions for multi-cation doped alpha-beta SiAlON ceramics by the Rietveld method
(Trans Tech Publications LTD, 2003)Although densification of alpha-beta-SiAlON ceramics is easier by using sintering additives, it is difficult to achieve the designed composition and therefore the mechanical properties after sintering. This is mainly due ... -
New developments in alpha-SiAlON ceramics
(Elsevier Sci LTD, 1999)Two different alpha-sialon compositions have been densified by either pressureless sintering or capsul-free sinter HIPing using either single cation namely strontium, lanthanum, cerium, neodymium or their equimolar mixtures ... -
The use of waste ceramic tile in cement production
(Pergamon-Elsevier Science LTD, 2000)In ceramic tile production, because of various reasons, unsold fired products come out. These are waste tiles and only a little part of them are used. Remainings create environmental problems. If these waste tiles are used ... -
Reactions at ceramic-metal interfaces in capacitor-discharge joined ceramics
(Transtec Publications LTD, 1999)A capacitor-discharge joining technique has been used to fabricate zirconia-AlxNiyYz zirconia (ZrO2) joints, in addition, the surface of the ZrO2 tiles were sputter coated with Ti and joined using Al as an interlayer ... -
Flextensional composite transducers: Designing, fabrication and application
(Springer, 2000)The design, fabrication and application of flextensional composite transducers are summarized in this study. The moonie and cymbal type flextensional transducer consist of a ceramic driving element sandwiched between two ... -
Improvement of sintering and microstructural homogeneity of a diphasic mullite
(Elsevier Sci LTD, 2001)Effect of seeding of boehmite-colloidal silica mixture with aluminium sulphate-colloidal silica mixture on its mullite formation and sintering behaviours and microstructural development was studied. It was observed that ...