SiO2 coated Ce2S3 red pigment was prepared in ethanol/H2O system via sol-gel method and TEOS were used as silica sources. X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy...SiO2 coated Ce2S3 red pigment was prepared in ethanol/H2O system via sol-gel method and TEOS were used as silica sources. X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDX）, UV-visible spectro-photometer and automatic colorimeter were used to investigate the properties of the samples. The results showed that the compact SiO2 film formed on the surface of Ce2S3 pigment at a cerium silicon molar ratio of 2. The thermal stability temperature of Ce2S3 pigment was improved to 450 oC after SiO2 coating. In addition, the color of Ce2S3 pigment was not affected significantly through coating colorless and transparent SiO2 and it could be used as safe red pigment in higher temperature fields.展开更多
The as-sintered sinter skin and the polished section of WC-11Co-0.4Cr 3 C 2-0.3VC-0.2RE（RE=mischmetal with La/Ce ratio of 0.65） alloy were analyzed.It was shown that the microstructures on the skin and in the inner ...The as-sintered sinter skin and the polished section of WC-11Co-0.4Cr 3 C 2-0.3VC-0.2RE（RE=mischmetal with La/Ce ratio of 0.65） alloy were analyzed.It was shown that the microstructures on the skin and in the inner part of the alloy were all characterized with a WC＋β＋M structure,where β was a cobalt-based binder phase and M represented a RE-containing phase.There existed an inward diffusion of S atoms,which caught and fixed the Ce atoms in the alloy and an outward diffusion of La atoms during the sintering process.Consequently,the M phase was characterized with the decreased La/Ce ratio（0.59） in the inner part and the increased La/Ce ratio（1.01） on the skin.The M phase on the skin was characterized with a γ-Ce 2 S 3 type structure.To suppress the long range migration of rare earth to the skin,S in the sintering atmosphere had to be eliminated.展开更多
基金Project supported by National Science and Technology Support Program(2011BAE30B03)Special Fund from Shaanxi Provincial Department of Education(12JK0467the Graduate Innovation Fund of Shaanxi Universityof Science and Technology for the financial support
文摘SiO2 coated Ce2S3 red pigment was prepared in ethanol/H2O system via sol-gel method and TEOS were used as silica sources. X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDX）, UV-visible spectro-photometer and automatic colorimeter were used to investigate the properties of the samples. The results showed that the compact SiO2 film formed on the surface of Ce2S3 pigment at a cerium silicon molar ratio of 2. The thermal stability temperature of Ce2S3 pigment was improved to 450 oC after SiO2 coating. In addition, the color of Ce2S3 pigment was not affected significantly through coating colorless and transparent SiO2 and it could be used as safe red pigment in higher temperature fields.
基金supported by National Natural Science Foundation of China (51074189,50823006)Science and Technology Planning Project Founda-tion of Hunan Province,China (2010FJ2006)+1 种基金Research Foundation for the Doctoral Program of Higher Education of China (20100162110001)the National Science & Technology Special Foundation of China (2011BAE09B02,2012ZX04003021)
文摘The as-sintered sinter skin and the polished section of WC-11Co-0.4Cr 3 C 2-0.3VC-0.2RE（RE=mischmetal with La/Ce ratio of 0.65） alloy were analyzed.It was shown that the microstructures on the skin and in the inner part of the alloy were all characterized with a WC＋β＋M structure,where β was a cobalt-based binder phase and M represented a RE-containing phase.There existed an inward diffusion of S atoms,which caught and fixed the Ce atoms in the alloy and an outward diffusion of La atoms during the sintering process.Consequently,the M phase was characterized with the decreased La/Ce ratio（0.59） in the inner part and the increased La/Ce ratio（1.01） on the skin.The M phase on the skin was characterized with a γ-Ce 2 S 3 type structure.To suppress the long range migration of rare earth to the skin,S in the sintering atmosphere had to be eliminated.
