The mechanical behavior of single-layer graphdiyne(SLGDY)subjected to high-velocity micro-ballistic impacts is analyzed by molecular dynamics(MD)simulations.The ballistic limits of SLGDY is obtained for the first time...The mechanical behavior of single-layer graphdiyne(SLGDY)subjected to high-velocity micro-ballistic impacts is analyzed by molecular dynamics(MD)simulations.The ballistic limits of SLGDY is obtained for the first time.The temperature deterioration effects of the impact resistance are also investigated.The results show that the ballistic limits can reach 75.4%of single-layer graphene(SLGR)at about 1/2 density,leading to approximately the same specific energy absorption(SEA)as SLGR.The ballistic limits of SLGDY and SLGR with single atomic thickness agree with the predictions of macroscopic penetration limits equations,implying the applicability of continuum penetration theories for two-dimensional(2D)materials.In addition,the dynamic responses involving stress wave propagation,conic deformation,and damage evolution are investigated to illuminate the mechanisms of the dynamic energy dissipation.The superior impact resistance of SLGDY and SLGR can be attributed to both the ultra-fast elastic and conic waves and the excellent deformation capabilities.This study provides a deep understanding of the impact behavior of SLGDY,indicating it is a promising protective material.展开更多
The fabrication of light-weight,highly impact-resistant,and energy-absorbent materials is urgently demanded in many facets of the society from body armor to aerospace engineering,especially under an extreme environmen...The fabrication of light-weight,highly impact-resistant,and energy-absorbent materials is urgently demanded in many facets of the society from body armor to aerospace engineering,especially under an extreme environment.Carbon nanotubes(CNTs),one of the strongest and toughest materials ever found,also have good conductivity,chemical stability,and thermal stability,etc,making them a competitive candidate as building blocks to help achieve the above goal.In this work,a kind of CNT network was prepared by using chlorosulfonic acid(CSA)to release the internal stress of super-aligned carbon nanotube films(SA-CNTF)and dendritic polyamide amine(PAMAM)to further introduce multiple hydrogen bonds and interlocking structures.The fabricated bioinspired carbon nanotube network films(PAMAM@C-CNTF)have a high toughness of 45.97 MJ/m3,showing an increase of 420%compared to neat SA-CNTF.More importantly,the anti-impact performance of the films(e.g.,with a maximum specific energy absorption of 1.40 MJ/kg under 80-100 m/s projectile impact)is superior to that of conventional protective materials from steel and Kevlar fiber,and also exceeds that of any other reported carbon-based materials.The hierarchical energy dissipation mechanism was further revealed through experiment and simulation.Additional functions including intelligent heating/anti-icing,ultraviolet protection,as well as electromagnetic interference shielding properties make these network films have great potential in practical multi-protection applications,especially under an extreme environment.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11672315,and 11772347)the Science Challenge Project(Grant No.TZ2018001)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDB22040302XDB22040303)。
文摘The mechanical behavior of single-layer graphdiyne(SLGDY)subjected to high-velocity micro-ballistic impacts is analyzed by molecular dynamics(MD)simulations.The ballistic limits of SLGDY is obtained for the first time.The temperature deterioration effects of the impact resistance are also investigated.The results show that the ballistic limits can reach 75.4%of single-layer graphene(SLGR)at about 1/2 density,leading to approximately the same specific energy absorption(SEA)as SLGR.The ballistic limits of SLGDY and SLGR with single atomic thickness agree with the predictions of macroscopic penetration limits equations,implying the applicability of continuum penetration theories for two-dimensional(2D)materials.In addition,the dynamic responses involving stress wave propagation,conic deformation,and damage evolution are investigated to illuminate the mechanisms of the dynamic energy dissipation.The superior impact resistance of SLGDY and SLGR can be attributed to both the ultra-fast elastic and conic waves and the excellent deformation capabilities.This study provides a deep understanding of the impact behavior of SLGDY,indicating it is a promising protective material.
基金supported by the National Key Basic Research Program of China(No.2022YFA1205400)the Chinese Postdoctoral Science Foundation(Nos.E1I41IR1 and E2911IR1).
文摘The fabrication of light-weight,highly impact-resistant,and energy-absorbent materials is urgently demanded in many facets of the society from body armor to aerospace engineering,especially under an extreme environment.Carbon nanotubes(CNTs),one of the strongest and toughest materials ever found,also have good conductivity,chemical stability,and thermal stability,etc,making them a competitive candidate as building blocks to help achieve the above goal.In this work,a kind of CNT network was prepared by using chlorosulfonic acid(CSA)to release the internal stress of super-aligned carbon nanotube films(SA-CNTF)and dendritic polyamide amine(PAMAM)to further introduce multiple hydrogen bonds and interlocking structures.The fabricated bioinspired carbon nanotube network films(PAMAM@C-CNTF)have a high toughness of 45.97 MJ/m3,showing an increase of 420%compared to neat SA-CNTF.More importantly,the anti-impact performance of the films(e.g.,with a maximum specific energy absorption of 1.40 MJ/kg under 80-100 m/s projectile impact)is superior to that of conventional protective materials from steel and Kevlar fiber,and also exceeds that of any other reported carbon-based materials.The hierarchical energy dissipation mechanism was further revealed through experiment and simulation.Additional functions including intelligent heating/anti-icing,ultraviolet protection,as well as electromagnetic interference shielding properties make these network films have great potential in practical multi-protection applications,especially under an extreme environment.
