To investigate the ballistic performance and damage characteristics of quasi threedimensional(3D) needle-punched Cf/SiC composites prepared by chemical vapor infiltration(CVI),penetration experiments were conducte...To investigate the ballistic performance and damage characteristics of quasi threedimensional(3D) needle-punched Cf/SiC composites prepared by chemical vapor infiltration(CVI),penetration experiments were conducted by using 7.62 mm armor piercing incendiary(API).Macro and micro fracture morphologies were then observed on recycled targets.The results show that the protection coefficient of 3D Cf/SiC composites is 2.54.High porosity and many micro thermal stress cracks may directly lead to the lower ballistic performance.Flat fracture morphology was observed on the crater surface.The low dynamic fracture strength along layer direction may be attributed to the voids and microcracks caused by residual thermal stress.The damage characteristics of Cf/Si C composites include matrix cracking,fiber bundle cracking,interfacial debonding,fiber fracture,and fiber bundle pull-out.And interfacial debonding and fiber fracture may play major roles in energy absorption.展开更多
In this paper, the fracture process of a unidirectional CF/SiCsingle edge-notched beam (SENB) under three-point bending (TPB) isstudied by means of macro/micro-statistical Monte Car- lo simulation.The simulated P-Δcu...In this paper, the fracture process of a unidirectional CF/SiCsingle edge-notched beam (SENB) under three-point bending (TPB) isstudied by means of macro/micro-statistical Monte Car- lo simulation.The simulated P-Δcurves are in agreement with the experimentalresults before the peaks of curves, and the simulated microevolutionpatterns are in agreement with the patterns of the crack surfaces,which have verified this method. It is preliminarily demonstratedthat the second turning point in the compliance changing rate curvecorresponds to the fracture initiation for experi- ments on SENBunder TPB of unidirectional CF/SiC composites.展开更多
基金Funded by the National Natural Science Foundation of China(No.51271036)
文摘To investigate the ballistic performance and damage characteristics of quasi threedimensional(3D) needle-punched Cf/SiC composites prepared by chemical vapor infiltration(CVI),penetration experiments were conducted by using 7.62 mm armor piercing incendiary(API).Macro and micro fracture morphologies were then observed on recycled targets.The results show that the protection coefficient of 3D Cf/SiC composites is 2.54.High porosity and many micro thermal stress cracks may directly lead to the lower ballistic performance.Flat fracture morphology was observed on the crater surface.The low dynamic fracture strength along layer direction may be attributed to the voids and microcracks caused by residual thermal stress.The damage characteristics of Cf/Si C composites include matrix cracking,fiber bundle cracking,interfacial debonding,fiber fracture,and fiber bundle pull-out.And interfacial debonding and fiber fracture may play major roles in energy absorption.
文摘In this paper, the fracture process of a unidirectional CF/SiCsingle edge-notched beam (SENB) under three-point bending (TPB) isstudied by means of macro/micro-statistical Monte Car- lo simulation.The simulated P-Δcurves are in agreement with the experimentalresults before the peaks of curves, and the simulated microevolutionpatterns are in agreement with the patterns of the crack surfaces,which have verified this method. It is preliminarily demonstratedthat the second turning point in the compliance changing rate curvecorresponds to the fracture initiation for experi- ments on SENBunder TPB of unidirectional CF/SiC composites.