抗冲击仿珍珠母陶瓷/金属复合板设计及其性能分析

Design and performance analysis of impact-resistant nacre-like ceramic/metal composite plates

陶瓷是常用的冲击防护材料,但其容易发生脆性破坏,在单独使用时抗冲击性能不佳,常需与金属等其他延性材料复合使用。模仿珍珠母的“砖-泥”式微观结构,以陶瓷片为“砖”、金属为“泥”,设计了仿珍珠母陶瓷/金属复合板。通过数值模拟分析了仿珍珠母复合板的抗平头弹冲击性能,将其与陶瓷板以及常见的陶瓷/金属层叠板进行了对比。结果表明:从弹体剩余速度来看,仿珍珠复合板的抗冲击性能显著优于陶瓷板,在金属体积比较小时也明显优于层叠板,但仿珍珠母复合板和层叠板的抗冲击性能差别随金属体积比的增加有缩小趋势;从保持结构完整性来看,仿珍珠母复合板也优于纯陶瓷板和层叠板,具有更好的抗多次冲击能力。仿珍珠母复合板的抗冲击性能优势主要来自侵彻过程的中间阶段,在侵彻过程后期、弹体接近靶板背面时,层叠板由于有背板对陶瓷碎片的约束作用,能提供相对更大的侵彻阻力。为了利用层叠板的这一优点,进一步设计了以仿珍珠母复合板为面板、金属板为背板的混合结构。通过对混合结构的抗冲击性能数值模拟,发现混合结构能得到比单独的仿珍珠母复合板更高的抗冲击性能,且存在一个中等大小的金属体积比使其抗冲击性能最大化。

Ceramic materials are commonly used for impact protection,but they are generally subjected to brittle failure and have poor impact resistance when they are used independently.This makes they necessary to combine with other ductile materials like metals.Nacre-like ceramic/metal composite plates were designed by mimicking the“brick-and-mortar”microstructure of nacre with ceramic tile as“brick”and metal as“mortar”.Impact resistance of the nacre-like plates was analyzed by numerical modelling and compared with ceramic plates and common layered ceramic/metal plates.The modelling results show that from the perspective of residual velocity of projectile,the nacre-like plates possess much better impact resistance performance than the ceramic plate,and also have obvious advantage over the layered plates when volume ratio of metal is relatively low,but difference between the performance of nacre-like composite plates and layered plates decreases as the volume ratio of metal increases.The advantage of nacre-like plates mainly results from the intermediate stage of the penetration process.When projectiles approach back faces of target plates at the later stage,layered composite plates can provide higher penetration resistance.To make use of this advantage of layered plates,hybrid structures were further designed by using a nacre-like composite plate as the cover plate and a metal plate as the backing plate.Through the numerical modelling of impact resistance of hybrid structures,it is found that they can produce higher impact resistance compared with nacre-like composite plates,and there is an intermediate volume ratio of metal to maximize their impact resistance.