Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
ceramicsVauchy, R.; Hirooka, Shun; Watanabe, Masashi; Yokoyama, Keisuke; Sunaoshi, Takeo*; Yamada, Tadahisa*; Nakamichi, Shinya; Murakami, Tatsutoshi
Ceramics International, 49(2), p.3058 - 3065, 2023/01
Times Cited Count：8 Percentile：75.06(Materials Science, Ceramics)Watanabe, Masashi; Yokoyama, Keisuke; Imai, Yoshiyuki; Ueta, Shohei; Yan, X.
Ceramics International, 48(6), p.8706 - 8708, 2022/03
Times Cited Count：7 Percentile：75.06(Materials Science, Ceramics)Previous studies have used various methods for sintering of SiC, carbon, and SiC/carbon functionally graded materials (FGM). However, no experimental studies on SiC/graphite FGM manufacturing using the spark plasma sintering (SPS) method have been reported. In this study, a SiC/graphite FGM specimen has been fabricated using SPS. The interface between the adjacent layers of the sintered specimen exhibits no apparent defects such as gaps or delaminations. The SiC and graphite phases in the specimen show no substantial change before and after sintering.
Tonegawa, Toru*; Ikoma, Toshiyuki*; Suetsugu, Yasushi*; Igawa, Naoki; Matsushita, Yoshitaka*; Yoshioka, Tomohiko*; Hanagata, Nobutaka*; Tanaka, Junzo*
Proceedings of 22nd International Symposium on Ceramics in Medicine (BIOCERAMICS-22), p.93 - 96, 2009/12
Hydroxyapatite is the main inorganic component of bone and tooth minerals, in which CO
ions partially substitute for OH and/or PO
ions. In this study, high purity type A carbonate apatite, Ca
(PO)
(CO)
powder completely substituted by carbonate ions were synthesized by a treatment of low crystalline hydroxyapatite powder, Ca(PO)(OH)
) in a dry CO flow at 1000 
C. The crystal structure of the sample was the monoclinic symmetry with space group of 
and the lattice parameters, 
= 0.9566 (1), 
= 1.9063 (2), 
= 0.6867 (1) nm and 
=119.84 (1), which was refined by a Rietveld method with neutron diffraction data.
Nozawa, Takashi; Tanigawa, Hiroyasu; Park, J.-S.*; Koyama, Akira*
Proceedings of 33rd International Conference on Advanced Ceramics and Composites (CD-ROM), p.65 - 76, 2009/09
SiC/SiC composites are promising candidate materials for various energy industries. One of key issues for their practical application is to develop design basis of quasi-ductile composites. Understanding the crack propagation behavior is therefore essential. For this purpose, determining a fracture resistances undoubtedly important and this paper aims to evaluate this using various types of notched specimens. With the preliminary analysis by the authors, a new methodology to determine the fracture resistance has been developed based on the non-linear fracture mechanics, separately discussing the effect of irreversible energies. By adopting this method for nano-infiltration transient-eutectic-phase sintered (NITE) SiC/SiC composites, several key findings were obtained: (1) notch insensitivity, (2) no significant size effect, and (3) superior crack tolerance.
Mannan, M. A.*; Nagano, Masamitsu*; Hirao, Norie*; Baba, Yuji
Proceedings of 24th Japan-Korea International Seminar on Ceramics, p.289 - 292, 2007/11
Boron carbonitride thin films were synthesized on Si(100) substrate by radiofrequency and microwave plasma enhanced vapor deposition using tris-dimethylamino borane as a precursor. The formation of the hexagonal phase of BCN films was confirmed by Fourier-transform infrared (FT-IR) spectroscopy. The measurements of X-ray photoelectron spectra (XPS) showed that boron atoms bonded to C and N atoms. The results for near edge X-ray absorption fine structures (NEXAFS) using synchrotron radiation supports the XPS results where B atoms bonded not only to nitrogen but also to carbon atoms to form various local structures. The polarization dependence of NEXAFS suggested that the local structures of BCN have different orientations in the films.
-MgO composite as surrogate for actinide-containing target for use in nuclear fuelOsaka, Masahiko; Miwa, Shuhei; Tachi, Yoshiaki
Ceramics International, 32(6), p.659 - 663, 2006/00
Times Cited Count：22 Percentile：80.19(Materials Science, Ceramics)A simple fabrication process for the fabrication of CeO-MgO composite as surrogate for actinide-containing target for the use in nuclear field is established. The process is adaptable to the present manufacturing technology for the nuclear fuel. The manufactured target have good characteristics, e.g. high density, good appearance etc. In particular, although the shape of CeO2 is not ideal sphere as expected but elliptic, thermal conductivity measurement results show that the elliptic shape is not disadvantageous. It means that the present simple process is comparable to that of rather complicated one, advanced sol-gel supported process.
and YVO laser crystalsSugiyama, Akira; Nara, Yasunaga
Ceramics International, 31(8), p.1085 - 1090, 2005/00
Times Cited Count：18 Percentile：78.81(Materials Science, Ceramics)We succeeded in the fabrication of bonded laser crystals composed of a neodymium-doped YVO laser crystal (Nd:YVO) and its host crystals YVO by a newly developed dry etching technique using an argon ion beam. The optical distortion caused by the bonded interface of size 5 mm 
6 mm was estimated to be 0.05-wave at 633 nm. From the comparison of laser performance pumped by a laser diode, the bonded crystals could increase the laser output power by nearly twice that of the non-bonded crystals with the same degree of polarization of 99.2 %. To analyze the mechanism of the enhanced reduction of the thermal load in the bonded crystals, numerical simulations with a finite-element method were also performed.
; *; ; ; ;
Ceramics International, 13, p.183 - 187, 1987/00
Times Cited Count：3 Percentile：38.26(Materials Science, Ceramics)no abstracts in English
