A stab-resistant substrate was designed and realized with a triangular pyramidal structure, inspired by the biological armor model in nature. The stab-resistance behavior and dynamic response mechanisms were studied t...A stab-resistant substrate was designed and realized with a triangular pyramidal structure, inspired by the biological armor model in nature. The stab-resistance behavior and dynamic response mechanisms were studied through numerical simulation and experimental testing of a knife impacting a substrate,and an optimal structural design was obtained accordingly, with a tilted angle of 22.5and optimal thickness of 1.2 mm. It was shown that the triangular pyramidal structure generated twice the internal energy of the knife than the flat substrate due to the dispersing effect of the structure. The force parallel to the inclination caused a significant scratch on the substrate surface, while the force perpendicular caused obvious substrate deformation. A new riveting method was used to form the total layer, which passed the GA 68-2008 standard. The stab-resistant clothing coupled with the reduced wearing burden could provide effective protection and avoid fatal injuries on security personnel working in dangerous environments. The method provided may enlighten the future design and manufacturing of stabresistant clothing.展开更多
Stab resistance body armor（SRBA）is essential in protecting people from knife injuries.The protective parts of traditional SRBA are made of multi-layered ultra-high molecular weight polyethylene（UHMWPE）,which cause...Stab resistance body armor（SRBA）is essential in protecting people from knife injuries.The protective parts of traditional SRBA are made of multi-layered ultra-high molecular weight polyethylene（UHMWPE）,which causes heavy heat stress for people wearing it.The protective parts of SRBA manufactured using laser sintering（LS）3D printing technology provide high manufacturing flexibility and low weight.Two different structures,plain plate and pyramid-structured plate,were investigated.The pyramid structure showed much higher stab resistance property then the plain plate,because of the angle and thickness effects.This is the first effort applying the LS technology and polyamide（PA）material（PA3200）on SRBA.By applying the pyramid structure on the protective layer of the SRBA,the total weight could reduce 30%-40%.展开更多
This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recen...This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recent evolution, and maturity, of the Ultra High Molecular Weight Polyethylene fibres enabling a completely new style of system to evolve e a stackable system of Hard Armour Plates. The science of body armour materials is quickly reviewed with emphasis upon current understanding of relevant energy-absorbing mechanisms in fibres, fabrics, polymeric laminates and ceramics. The trend in ongoing developments in ballistic fibres is then reviewed, analysed and future projections offered. Weaknesses in some of the ceramic grades are highlighted as is the value of using cladding materials to improve the robustness, and multi-strike performance, of Hard Armour Plates. Finally, with the drive for lighter, and therefore smaller, soft armour systems for military personnel the challenges for armour designers are reported, and the importance of the relative size of the Hard Armour Plate to the Soft Armour Insert is strongly emphasised.展开更多
Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of BABT.Comparison of pressure wave i...Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of BABT.Comparison of pressure wave in the gelatin behind armor for different rifle bullets is lacking.The aim of this study was to observe dynamic changes in pressure wave induced by ballistic blunt impact on the armored gelatin block and to compare the effects of bullet type on the parameters of the transient pressure wave.The gelatin blocks protected with National Institute of Justice(NIJ) class III bulletproof armor were shot by three types of rifle bullet with the same level of impact energy.The transient pressure signals at five locations were recorded with pressure sensors and three parameters(maximum pressure,maximum pressure impulse,and the duration of the first positive phase) were determined and discussed.The results indicated that the waveform and the twin peak of transient pressure wave were not related to the bullet type.However,the values of pressure wave's parameters were significantly affected by bullet type.Additionally,the attenuation of pressure amplitude followed the similar law for the three ammunitions.These findings may be helpful to get some insight in the BABT and improve the structure design of bullet.展开更多
The ballistic performance,and behaviour,of an armour system is governed by two major sets of variables,geometrical and material.Of these,the consistency of performance,especially against small arms ammunition,will dep...The ballistic performance,and behaviour,of an armour system is governed by two major sets of variables,geometrical and material.Of these,the consistency of performance,especially against small arms ammunition,will depend upon the consistency of the properties of the constituent materials.In a body armour system for example,fibre diameter,areal density of woven fabric,and bulk density of ceramic are examples of critical parameters and monitoring such parameters will form the backbone of associated quality control procedures.What is often overlooked,because it can fall into the User’s domain,are the interfaces that exist between the various products;the carrier,the Soft Armour Insert(SAI),and the one or two hard armour plates(HAP1 and HAP2).This is especially true if the various products are sourced from different suppliers.展开更多
基金supported by the National Natural Science Foundation of China [51874041 and 71861167002]。
文摘A stab-resistant substrate was designed and realized with a triangular pyramidal structure, inspired by the biological armor model in nature. The stab-resistance behavior and dynamic response mechanisms were studied through numerical simulation and experimental testing of a knife impacting a substrate,and an optimal structural design was obtained accordingly, with a tilted angle of 22.5and optimal thickness of 1.2 mm. It was shown that the triangular pyramidal structure generated twice the internal energy of the knife than the flat substrate due to the dispersing effect of the structure. The force parallel to the inclination caused a significant scratch on the substrate surface, while the force perpendicular caused obvious substrate deformation. A new riveting method was used to form the total layer, which passed the GA 68-2008 standard. The stab-resistant clothing coupled with the reduced wearing burden could provide effective protection and avoid fatal injuries on security personnel working in dangerous environments. The method provided may enlighten the future design and manufacturing of stabresistant clothing.
基金Supported by the Independent Research Project of State Key Laboratory of Explosion Science and Technology(YBKT16-13)Beijing Institute of Technology Research Fund Program for Young Scholars(2-205205-2014)National Key Rsearch Program(2016YFC0802801-4)
文摘Stab resistance body armor（SRBA）is essential in protecting people from knife injuries.The protective parts of traditional SRBA are made of multi-layered ultra-high molecular weight polyethylene（UHMWPE）,which causes heavy heat stress for people wearing it.The protective parts of SRBA manufactured using laser sintering（LS）3D printing technology provide high manufacturing flexibility and low weight.Two different structures,plain plate and pyramid-structured plate,were investigated.The pyramid structure showed much higher stab resistance property then the plain plate,because of the angle and thickness effects.This is the first effort applying the LS technology and polyamide（PA）material（PA3200）on SRBA.By applying the pyramid structure on the protective layer of the SRBA,the total weight could reduce 30%-40%.
文摘This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recent evolution, and maturity, of the Ultra High Molecular Weight Polyethylene fibres enabling a completely new style of system to evolve e a stackable system of Hard Armour Plates. The science of body armour materials is quickly reviewed with emphasis upon current understanding of relevant energy-absorbing mechanisms in fibres, fabrics, polymeric laminates and ceramics. The trend in ongoing developments in ballistic fibres is then reviewed, analysed and future projections offered. Weaknesses in some of the ceramic grades are highlighted as is the value of using cladding materials to improve the robustness, and multi-strike performance, of Hard Armour Plates. Finally, with the drive for lighter, and therefore smaller, soft armour systems for military personnel the challenges for armour designers are reported, and the importance of the relative size of the Hard Armour Plate to the Soft Armour Insert is strongly emphasised.
基金supported by the National Basic Scientific Research Project(Grant NO.JCKYS2019209C001)National Key Research and Development Program of China(Grant NO.2017YFC0822301&Grant NO.2018YFC0807206)National Natural Science Foundation of China(Grant NO.11772303)。
文摘Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of BABT.Comparison of pressure wave in the gelatin behind armor for different rifle bullets is lacking.The aim of this study was to observe dynamic changes in pressure wave induced by ballistic blunt impact on the armored gelatin block and to compare the effects of bullet type on the parameters of the transient pressure wave.The gelatin blocks protected with National Institute of Justice(NIJ) class III bulletproof armor were shot by three types of rifle bullet with the same level of impact energy.The transient pressure signals at five locations were recorded with pressure sensors and three parameters(maximum pressure,maximum pressure impulse,and the duration of the first positive phase) were determined and discussed.The results indicated that the waveform and the twin peak of transient pressure wave were not related to the bullet type.However,the values of pressure wave's parameters were significantly affected by bullet type.Additionally,the attenuation of pressure amplitude followed the similar law for the three ammunitions.These findings may be helpful to get some insight in the BABT and improve the structure design of bullet.
文摘The ballistic performance,and behaviour,of an armour system is governed by two major sets of variables,geometrical and material.Of these,the consistency of performance,especially against small arms ammunition,will depend upon the consistency of the properties of the constituent materials.In a body armour system for example,fibre diameter,areal density of woven fabric,and bulk density of ceramic are examples of critical parameters and monitoring such parameters will form the backbone of associated quality control procedures.What is often overlooked,because it can fall into the User’s domain,are the interfaces that exist between the various products;the carrier,the Soft Armour Insert(SAI),and the one or two hard armour plates(HAP1 and HAP2).This is especially true if the various products are sourced from different suppliers.
