Abstract: The present paper is focused on ceramic–metal composites obtained via different
technologies which leads to different microstructures in terms of size and distribution of metal phase. Composites analysed in paper were produced by the following methods:(a) infiltration of porous ceramics by metal, (b) consolidation under high pressure and (c) sintering of ceramic powder coated by metal. Their microstructures were investigated by scanning and transmission electron microscopy methods. The three methods of composite fabrication employed in the present study result in specific spatial distribution and dispersion of metal phase. Presureless infiltration of porous ceramics by liquid metal is driven by capillary force and make it possible to produce microstructure with percolation of metal phase in ceramic matrix. The volume fraction of metal phase in this case depends on the size
of pores. The size of pores influence also the kinetics and extent of infiltration. Ceramic preforms with small size of pore are not fully infiltrated. This method is useful for composite with size of metal phase in the range of micrometers. Hot pressing under high pressure produces microstructures of composites with metal phase grain size in the range from nano to micrometers. Moreover, it allows to achieve the nanometric size of ceramic grains. In the case of ceramic powders covered by metal, compression and hot pressing preserves nanometric size of metal. The grain growth of ceramic grains is suppressed.
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.
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.
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.