caa a22 4500 463227441 CHVBK 20180405153231.0 cr unu---uuuuu 170326e20070501xx s 000 0 eng 10.1007/s10853-006-0384-1 doi (NATIONALLICENCE)springer-10.1007/s10853-006-0384-1 SiCf/SiC composites reinforced by randomly oriented chopped fibers prepared by semi-solid mechanical stirring method and hot pressing [Elektronische Daten] [X. Qin, B. Xiao, S. Dong, D. Jiang] SiC short fibers, with an average diameter of 13μm, length of 300-1,000μm and chopped from SiC continuous fibers, were surface modified by the semi-solid mechanical stirring method to produce a discrete coating of aluminum particles. Then the starting mixtures, which consist of SiC short composite fibers, aluminum powder less than 50μm and α-SiC powder of an average diameter of 0.6μm, were mechanically mixed in ethanol for about 3h, dried at 80°C in air, and hot pressed under 30MPa pressure at 1,650, 1,750 and 1,850°C with 1h holding time to prepare SiCf/SiC composites. Volume fraction of SiC short fibers in the starting powder for SiCf/SiC composites was about 25vol.%. The composites were characterized in terms of bulk density, phase composition, and mechanical properties at room temperature. In addition, the distribution of SiC short fibers in the matrix and the cracking pattern in the composites were examined by optical microscope. Fracture surface of the composites were performed by a scanning electron microscope (SEM). The effect of hot-pressing temperature on bulk density and mechanical properties was investigated. The results indicated that SiC short fibers were uniformly and randomly distributed in the matrix, bending strength and bulk density of the composites increased with increasing sintering temperature. The composite, hot-pressed at 1,850°C, exhibited the maximum bulk density and bending strength at room temperature, about 3.01g/cm3 and 366MPa, respectively. SEM analyses showed that there were a few of fiber pullout on the fracture surface of samples sintered at 1,650°C and 1,750°C, which was mainly attributed to lower densities. But few of fiber pullout was observed on the fracture surface of sample sintered at 1,850°C, the combined effects of high temperature and a long sintering time were considered as a source of too severe fiber degradation because of the large amount of oxygen in the fibers. Springer Science+Business Media, LLC, 2007 Qin X. Research Institute for Stainless Steel, R & D Center, Baoshan Iron & Steel Co.,, No.655 Fujin Road, Baoshan District, 201900, Shanghai, China aut Xiao B. General Research Institute for Nonferrous Metals, 100088, Beijing, China aut Dong S. Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai, China aut Jiang D. Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai, China aut Journal of Materials Science Springer US; http://www.springer-ny.com 42/10(2007-05-01), 3488-3494 0022-2461 42:10<3488 2007 42 10853 https://doi.org/10.1007/s10853-006-0384-1 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-006-0384-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Qin X. Research Institute for Stainless Steel, R & D Center, Baoshan Iron & Steel Co.,, No.655 Fujin Road, Baoshan District, 201900, Shanghai, China aut NATIONALLICENCE 700 1- Xiao B. General Research Institute for Nonferrous Metals, 100088, Beijing, China aut NATIONALLICENCE 700 1- Dong S. Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai, China aut NATIONALLICENCE 700 1- Jiang D. Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, Shanghai, China aut NATIONALLICENCE 773 0- Journal of Materials Science Springer US; http://www.springer-ny.com 42/10(2007-05-01), 3488-3494 0022-2461 42:10<3488 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer