In the present work, novolac phenolic resin-based composites reinforced with short discrete carbon fibers were pyrolized at different temperatures from 400℃ to 900℃. Their physical and chemical properties were studi...In the present work, novolac phenolic resin-based composites reinforced with short discrete carbon fibers were pyrolized at different temperatures from 400℃ to 900℃. Their physical and chemical properties were studied, linterfacial bonding between the matrix and carbon fiber and its influence on mechanical properties of analyzed composites were analyzed. Experimental results demonstrated strengthening of interfacial bonding with increase of pyrolysis temperature. Evolution of failure behavior was observed.展开更多
Silicon oxycarbide composites reinforced by three-dimensional braided carbon fiber （3D-B Cf/Si-O-C） were fabricated via precursor infiltration and pyrolysis of polysiloxane, and the effects of processing variables o...Silicon oxycarbide composites reinforced by three-dimensional braided carbon fiber （3D-B Cf/Si-O-C） were fabricated via precursor infiltration and pyrolysis of polysiloxane, and the effects of processing variables on mechanical properties and microstructures of 3D-B Cf/Si-O-C composites were investigated. It is found that the mechanical properties and densities of 3D-B Cf/Si-O-C composites can be increased if the first pyrolysis cycle is assisted by hot-pressing. Pyrolysis temperature has great effects on mechanical properties and microstructures of 3D-B Cf/Si-O-C composites. The composite, which is hot-pressed at 1 600 ℃ for 5 min with pressure of 10 MPa in the first pyrolysis cycle, exhibits high mechanical properties: bending strength 502 MPa and fracture toughness 23.7 MPa·m1/2. The high mechanical properties are mainly attributed to desirable interfacial structure and high density.展开更多
文摘In the present work, novolac phenolic resin-based composites reinforced with short discrete carbon fibers were pyrolized at different temperatures from 400℃ to 900℃. Their physical and chemical properties were studied, linterfacial bonding between the matrix and carbon fiber and its influence on mechanical properties of analyzed composites were analyzed. Experimental results demonstrated strengthening of interfacial bonding with increase of pyrolysis temperature. Evolution of failure behavior was observed.
文摘Silicon oxycarbide composites reinforced by three-dimensional braided carbon fiber （3D-B Cf/Si-O-C） were fabricated via precursor infiltration and pyrolysis of polysiloxane, and the effects of processing variables on mechanical properties and microstructures of 3D-B Cf/Si-O-C composites were investigated. It is found that the mechanical properties and densities of 3D-B Cf/Si-O-C composites can be increased if the first pyrolysis cycle is assisted by hot-pressing. Pyrolysis temperature has great effects on mechanical properties and microstructures of 3D-B Cf/Si-O-C composites. The composite, which is hot-pressed at 1 600 ℃ for 5 min with pressure of 10 MPa in the first pyrolysis cycle, exhibits high mechanical properties: bending strength 502 MPa and fracture toughness 23.7 MPa·m1/2. The high mechanical properties are mainly attributed to desirable interfacial structure and high density.
