The performance of composite ceramic armor penetrated by rod projectile was studied by both numerical simulation and experiment.The penetration and damage mechanisms of the projectile-armor after high-speed collision ...The performance of composite ceramic armor penetrated by rod projectile was studied by both numerical simulation and experiment.The penetration and damage mechanisms of the projectile-armor after high-speed collision were also observed by high-speed photography.The experimental results showed that the ballistic performance of composite ceramic armor was highly affected by the density,hardness and toughness of bulletproof ceramic.The flow stress of the failed bulletproof ceramic is not only related to the pressure but also related to the strain rate.The phenomenological method based on Bodner-Partom ceramic model was introduced to derive the growth rate of damage.Numerical simulation results show good agreement with the experimental results.展开更多
The B4C matrix composite intended for armor applications still presents restrictions,such as low sintering density,production of large parts and inherited brittleness Herein,research on this topic is discussed in deta...The B4C matrix composite intended for armor applications still presents restrictions,such as low sintering density,production of large parts and inherited brittleness Herein,research on this topic is discussed in detail.First the material outlook of armor applications is organized from the development of composite armor and ceramic materials for armor to the B4C matrix composite and reactive-sintering method.In the second section,the technologies are reviewed for reactive pressureless sintering reactive hot-pressing sintering,reactive discharge plasma sintering and self-propagating high-temperature sintering Thereafter,our previous works on the TiB2/SiC/B4C composite and laminated Ti/B4C composite are employed to illustrate their microstructural evolution,phase transformation and fracture model.These studies provide a potential method for producing tough and high-strength ceramic composites for armor application.In the fina section,the mechanism,evaluation method and influencing factors of anti-penetration for ceramic armor and B4C matrix composite are reviewed.展开更多
The use of carbon nanotubes in composite hard armor is discussed in this study.The processing techniques to make various armor composite panels consisting of Kevlar■29 woven fabric in an epoxy matrix and the subseque...The use of carbon nanotubes in composite hard armor is discussed in this study.The processing techniques to make various armor composite panels consisting of Kevlar■29 woven fabric in an epoxy matrix and the subsequent V50 test results for both 44 caliber soft-point rounds and 30 caliber FSP(fragment simulated projectile)threats are presented.A 6.5%improvement in the V50 test results was found for a combination of 1.65 wt%loading of carbon nanotubes and 1.65 wt%loading of milled fibers.The failure mechanism of carbon nanotubes during the ballistic event is discussed through scanning electron microscope images of the panels after the failure.Raman Spectroscopy was also utilized to evaluate the residual strain in the Kevlar■29 fibers post shoot.The Raman Spectroscopy shows a Raman shift of 25 cm^(−1) for the Kevlar■29 fiber utilized in the composite panel that had an enhancement in the V50 performance by using milled fiber and multi-walled carbon nanotubes.Evaluating both scenarios where an improvement was made and other panels without any improvement allows for understanding of how loading levels and synergistic effects between carbon nanotubes and milled fibers can further enhance ballistic performance.展开更多
文摘The performance of composite ceramic armor penetrated by rod projectile was studied by both numerical simulation and experiment.The penetration and damage mechanisms of the projectile-armor after high-speed collision were also observed by high-speed photography.The experimental results showed that the ballistic performance of composite ceramic armor was highly affected by the density,hardness and toughness of bulletproof ceramic.The flow stress of the failed bulletproof ceramic is not only related to the pressure but also related to the strain rate.The phenomenological method based on Bodner-Partom ceramic model was introduced to derive the growth rate of damage.Numerical simulation results show good agreement with the experimental results.
基金financially supported by the Opening Project of Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology(No.ASMA201909)the Scientific Research Foundation for the High-level Talents of Nanjing Institute of Technology(No.YKJ201958)the Outstanding Scientific and Technological Innovation Team in Colleges and Universities of Jiangsu Province。
文摘The B4C matrix composite intended for armor applications still presents restrictions,such as low sintering density,production of large parts and inherited brittleness Herein,research on this topic is discussed in detail.First the material outlook of armor applications is organized from the development of composite armor and ceramic materials for armor to the B4C matrix composite and reactive-sintering method.In the second section,the technologies are reviewed for reactive pressureless sintering reactive hot-pressing sintering,reactive discharge plasma sintering and self-propagating high-temperature sintering Thereafter,our previous works on the TiB2/SiC/B4C composite and laminated Ti/B4C composite are employed to illustrate their microstructural evolution,phase transformation and fracture model.These studies provide a potential method for producing tough and high-strength ceramic composites for armor application.In the fina section,the mechanism,evaluation method and influencing factors of anti-penetration for ceramic armor and B4C matrix composite are reviewed.
基金supported by Florida Space Grant Consortium(FSGC)under grant number NASA NNX10AM01H.
文摘The use of carbon nanotubes in composite hard armor is discussed in this study.The processing techniques to make various armor composite panels consisting of Kevlar■29 woven fabric in an epoxy matrix and the subsequent V50 test results for both 44 caliber soft-point rounds and 30 caliber FSP(fragment simulated projectile)threats are presented.A 6.5%improvement in the V50 test results was found for a combination of 1.65 wt%loading of carbon nanotubes and 1.65 wt%loading of milled fibers.The failure mechanism of carbon nanotubes during the ballistic event is discussed through scanning electron microscope images of the panels after the failure.Raman Spectroscopy was also utilized to evaluate the residual strain in the Kevlar■29 fibers post shoot.The Raman Spectroscopy shows a Raman shift of 25 cm^(−1) for the Kevlar■29 fiber utilized in the composite panel that had an enhancement in the V50 performance by using milled fiber and multi-walled carbon nanotubes.Evaluating both scenarios where an improvement was made and other panels without any improvement allows for understanding of how loading levels and synergistic effects between carbon nanotubes and milled fibers can further enhance ballistic performance.