Flexural properties and fracture mechanism of 3D four-directional braided (SiO2)f/SiO2 composites prepared by silica sol-infiltration-sintering method
3D four directional braided (SiO2)f/SiO2 composites were prepared by silicasol-infiltration-sintering method.The specimen density was determined to be 1.71 g/cm3 by using the Archimedes principle.The flexural properties were evaluated by three-point bending test.The flexural strength and flexural elastic modulus were found to be 62 MPa and 11 GPa,respectively.The stress vs.deflection curve showed a typical composite behavior,initially a linear elastic response,followed a nonlinear region and finally failed gracefully.The SEM micrograph of the fracture sections showed extensive fibers pull-out,indicating the composites exhibited good toughness.A distinctly crevice was observed along the interfacial region,indicating the weak interfacial bonding between fiber and matrix,resulting in extensive fibers pull-out with a failure strain.The results of stress vs.deflection and SEM examination revealed that the fracture mechanism of the (SiO2)f/SiO2 composite was a mixed mode of brittle and ductile.
3D four-directional (SiO2)f/SiO2 composites silica sol-infiltration-sintering process flexural properties fracture mechanism
Li Binbin Zhu Jianxun Chen Zhaofeng Boafo FredEdmond Jiang Yun Hu Fangtian
College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanj College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanj Sinamo Science and Technology Company Limited, Nanjing, 210013, P.R.China
国际会议
上海
英文
36-36
2012-10-19（万方平台首次上网日期，不代表论文的发表时间）