Authors: Jun Ping Yan, Zi Long Tang, Shao Hua Luo, Zhong Tai Zhang
Abstract: Sr4Al14O25: Eu2+, Dy3+ luminescent ceramics with high brightness and long afterglow were
prepared using glass frits as binders by sintering at lower temperature and air atmosphere. The effects of
glass frits on the properties of luminescent ceramics were discussed. The analytical results indicate that
the surface structure and adhesion with phosphor are influenced by glass frits and sintering temperature.
When sintered at 850°C, the samples with frit1 or frit2 obtained good surface morphology and good
adhesion. The sample with frit2 sintered at 850°C yielded the better surface morphology and good
adhesion. The sample with frit1 sintering at 850°C possessed the better luminescent properties.
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Authors: Daisuke Horikawa, Junichi Tatami, Toru Wakihara, Katsutoshi Komeya, Takeshi Meguro
Abstract: HfO2-added Si3N4 ceramics are known to exhibit excellent high-temperature strength and excellent damage characteristics because HfO2 assists the crystallization of the grain boundary phase. However, the sintering shrinkage behavior and mechanical properties of HfO2-added Si3N4 have not been well clarified so far, although it has been reported that TiO2, in which Ti is from the same group as Hf in the periodic table, enhances the densification of the Si3N4-Y2O3-Al2O3-AlN system and wear resistance due to TiN formed from TiO2 and AlN in the grain boundary. In the present study, we focus on HfO2 as the sintering aid to investigate the sintering shrinkage behavior and mechanical properties of HfO2-added Si3N4. The powder mixtures are prepared by the addition of HfO2 to the Si3N4-Y2O3-Al2O3 or Si3N4-Y2O3-Al2O3-AlN system. The sintering shrinkage curves of HfO2-added Si3N4 ceramics show rapid shrinkage at 1600°C as compared with those of the Si3N4 ceramics without HfO2.The shrinkage can be explained by the formation of SiO2-Y2O3-HfO2 derived liquid phases. Furthermore, the mechanical properties of HfO2-added Si3N4 were as excellent as those of the Si3N4 ceramics without HfO2.
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Authors: Sha Li, Hai Yan Du, Duo Yang, Ji Ping Guo, Di Song, Gui Yan Li
Abstract: Porous SiO2 ceramics had been successfully prepared by gelcasting. The open porosity of obtained samples was between 0.40 and 0.46, which reached its maximum at 1100°C. The change of line shrinkage rate was opposite to the open porosity. The microstructure was investigated though X-ray diffraction (XRD) and scanning electronic microscope (SEM).
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Authors: You Jun Lu, Hong Fang Shen, Yan Ming Wang
Abstract: High-temperature mechanical properties, machinability, oxidation resistance and thermal shock resistance of different content of carbon particles modified silicon carbide composite ceramics (Cp/SiC) prepared by pressureless sintering techniques were studied. Adhesion of Cp/SiC to melted glass under 1000°C was also observed. The results showed that 15-Cp/SiC had the optimum machinability and it also did not adhere to melted glass at high temperature. And flexural strength, hardness, and fracture toughness of 15-Cp/SiC is 136.5MPa, 274.6kgf/mm2, 2.58MPa•m1/2 respectively. The good performance of Cp/SiC made it possible to be used as high temperature glass fixture, which means that Cp/SiC can not only improve the service life of fixture materials, but also broaden the application fields of SiC ceramics.
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Authors: Yun Yun Xu, Xin Nian Li, Shan Dan Zhou, Tao Zhang, Zheng Ming Li
Abstract: Inorganic non-metallic materials are indispensable and fundamental materials to develop modern industry, agriculture, national defense and science and technology. With the recovery and development of global economy, inorganic non-metallic materials come close to important program opportunity. This paper reviewed recent development on inorganic non-metallic materials technology and industry and analyzed development trend, aimed at providing references for development on inorganic non-metallic technology and industry in Jiangxi province.
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