摘要
陶瓷复合装甲主要由陶瓷层和背板层组成,广泛应用于冲击防护.然而,目前仍缺乏背板层在提高陶瓷复合装甲系统防弹性能方面的定量认识和分析.本文以B4C/UHMWPE双层装甲体系为例,从理论上系统地研究了UHMWPE层在提高陶瓷复合装甲弹道阻力方面的增强机理和适合UHMWPE厚度的选取.开发并验证了预测双层装甲系统剩余速度的理论模型.具体而言,分别从理论上获得与塑性、断裂和摩擦相关的耗散能以及由弹性应变能和动能组成的储存能.理论结果表明,随着UHMWPE层厚度的增加,耗散能单调增加,而储存能则先增加后减少,并会出现一个转折点,这是由于储存能的主导机制由系统固有的最大储存能转变为剩余动能.此外,对于给定的弹道阻力,根据存储能的转变提出了为降低面密度的最佳UHMWPE厚度的参考值,这与陶瓷厚度、冲击速度和弹丸质量有关.本文的研究有助于指导陶瓷复合装甲的轻量化设计.
Ceramic composite armor,mainly composed of ceramic and backing layers,has been widely used in impact protection.However,the quantitative understanding and analysis for the role of the backing layer in improving the ballistic resistance of the ceramic composite armor system is still lacking.In this paper,by taking the B4C/UHMWPE bi-layer armor system as an example,the enhanced mechanism of the UHMWPE layer in improving the ballistic resistance of the ceramic composite armor and the appropriate UHMWPE thickness are systematically studied theoretically.A theoretical model predicting the residual velocity of a bi-layer armor system is developed and verified.Specifically,the dissipated energy associated with plasticity,fracture and friction and the stored energy composed of the elastic strain energy and kinetic energy,is theoretically obtained,respectively.The theoretical results show that as the increase of the UHMWPE thickness,the dissipated energy monotonically increases,while the stored energy first increases and then decreases with the appearance of a turning point due to the dominant mechanism of the stored energy changing from the maximum stored energy of the system inherently to residual kinetic energy.Furthermore,for a given ballistic resistance,a reference value for the optimal UHMWPE thickness to lower the areal density is proposed according to the transition of the stored energy,which is related to the ceramic thickness,impact velocity and the mass of the projectile.The study in this paper helps guide the lightweight design of ceramic composite armor.
作者
杨尚霖
王毅刚
张逸之
柳占立
Shanglin Yang;Yigang Wang;Yizhi Zhang;Zhanli Liu(Applied Mechanics Laboratory,Department of Engineering Mechanics,School of Aerospace Engineering,Tsinghua University,Beijing 100084,China)
基金
supported by the National Natural Science Foundation of China (Grant Nos.11972205,11921002,and 11972210).
