Ceramic matrix composites (CMCs) are the preferred materials for solving advanced aerospace high-temperature structural components;it has the comprehensive advantages of higher temperature (~1500˚C) and low density. I...Ceramic matrix composites (CMCs) are the preferred materials for solving advanced aerospace high-temperature structural components;it has the comprehensive advantages of higher temperature (~1500˚C) and low density. In service environments, CMCs exhibit complex damage mechanisms and failure modes, which are affected by constituent materials, meso-architecture and inhere defects. In this paper, the in-plane tensile mechanical behavior of a plain-woven SiCf/SiC composite at room and elevated temperatures was investigated, and the factors affecting the tensile strength of the material were discussed in depth. The results show that the tensile modulus and strength of SiCf/SiC composites at high temperature are lower, but the fracture strain increases and the toughness of the composites is enhanced;the stitching holes significantly weaken the tensile strength of the material, resulting in the material is easy to break at the cross-section with stitching holes.展开更多
C f/SiC composites were prepared by precursor pyrolysis hot pressing, and the effect of fiber characteristics on the fracture behavior of the composites was investigated. Because the heat treatment temperature of fibe...C f/SiC composites were prepared by precursor pyrolysis hot pressing, and the effect of fiber characteristics on the fracture behavior of the composites was investigated. Because the heat treatment temperature of fiber T300 (below 1?500?℃) was much lower than that of fiber M40JB (over 2?000?℃), fiber T300 had lower degree of graphitization and consisted of more impurities compared with fiber M40JB, suggesting that T300 exhibits higher chemical activity. As a result, the composite with T300 showed a brittle fracture behavior, which is mainly ascribed to a strongly bonded fiber/matrix interface as well as the degradation of fibers during the preparation of the composite. However, the composite with M40JB exhibits a tough fracture behavior, which is primarily attributed to a weakly bonded fiber/matrix interface and higher strength retention of the fibers.展开更多
概述了国外碳化硅连续纤维增强钛基复合材料的研制、性能及应用情况 ,并对箔压法制备 Si Cf/Ti复合材料的工艺及材料性能进行了研究。结果表明 ,本研究采用 FFF法制作的 Si Cf/Ti复合板材性能达到国外同类材料水平。此外 ,本研究还对 Si...概述了国外碳化硅连续纤维增强钛基复合材料的研制、性能及应用情况 ,并对箔压法制备 Si Cf/Ti复合材料的工艺及材料性能进行了研究。结果表明 ,本研究采用 FFF法制作的 Si Cf/Ti复合板材性能达到国外同类材料水平。此外 ,本研究还对 Si Cf/Ti复合材料各主要制作工艺进行了分析比较 ,认为真空等离子喷涂工艺是较有前途的。展开更多
文摘Ceramic matrix composites (CMCs) are the preferred materials for solving advanced aerospace high-temperature structural components;it has the comprehensive advantages of higher temperature (~1500˚C) and low density. In service environments, CMCs exhibit complex damage mechanisms and failure modes, which are affected by constituent materials, meso-architecture and inhere defects. In this paper, the in-plane tensile mechanical behavior of a plain-woven SiCf/SiC composite at room and elevated temperatures was investigated, and the factors affecting the tensile strength of the material were discussed in depth. The results show that the tensile modulus and strength of SiCf/SiC composites at high temperature are lower, but the fracture strain increases and the toughness of the composites is enhanced;the stitching holes significantly weaken the tensile strength of the material, resulting in the material is easy to break at the cross-section with stitching holes.
文摘C f/SiC composites were prepared by precursor pyrolysis hot pressing, and the effect of fiber characteristics on the fracture behavior of the composites was investigated. Because the heat treatment temperature of fiber T300 (below 1?500?℃) was much lower than that of fiber M40JB (over 2?000?℃), fiber T300 had lower degree of graphitization and consisted of more impurities compared with fiber M40JB, suggesting that T300 exhibits higher chemical activity. As a result, the composite with T300 showed a brittle fracture behavior, which is mainly ascribed to a strongly bonded fiber/matrix interface as well as the degradation of fibers during the preparation of the composite. However, the composite with M40JB exhibits a tough fracture behavior, which is primarily attributed to a weakly bonded fiber/matrix interface and higher strength retention of the fibers.
文摘概述了国外碳化硅连续纤维增强钛基复合材料的研制、性能及应用情况 ,并对箔压法制备 Si Cf/Ti复合材料的工艺及材料性能进行了研究。结果表明 ,本研究采用 FFF法制作的 Si Cf/Ti复合板材性能达到国外同类材料水平。此外 ,本研究还对 Si Cf/Ti复合材料各主要制作工艺进行了分析比较 ,认为真空等离子喷涂工艺是较有前途的。
