高性能硼化物陶瓷在强动载荷作用下的失效行为与机制分析

高性能硼化物陶瓷作为新一代抗弹陶瓷具有高硬度、低密度、可加工等优异特性，是当前抗弹陶瓷研究的热点。但是，目前研究工作主要采用唯象损伤力学和有限元方法模拟材料宏观层面的破坏行为，忽略了材料在冲击加载过程中细观层次的微结构的变化，因此，高性能硼化物陶瓷在高速、强冲击加载条件下的材料结构演变和力学响应行为的尚不清楚，导致对材料的失效行为难以解释清楚。本项目拟以实验为主，重点研究细观层次下对TiB2和B4C的复相陶瓷材料在强动载荷和高能量密度冲击下的陶瓷晶体结构的演变，弄清TiB2和B4C陶瓷各自的损伤规律，以及TiB2和B4C陶瓷损伤的相互联系；其次，结合数值模拟，利用基于密度泛函数的晶体相场理论模拟研究TiB2和B4C陶瓷晶体结构和键价的变化，揭示陶瓷结构变化与材料失效行为间的关系，为高性能硼化物陶瓷的结构设计提供基础支撑。

Exhibiting high desirable features such as high hardness, low density, good workability, high-performance boride ceramic can be applied as a new generation bulletproof ceramic that becoming research hotspot. However, in the previous research, the researchers focus on simulating destructive behavior of material in macroscopic scale using phenomenological damage mechanics and finite element method, ignoring the microstructural variation on meso-level in impact loading of material that resulted in failure behaviors. Therefore, the research about material structural evolution and mechanical response behavior of high-performance boride ceramic under high speed and strong impact loading condition was not clear yet. In this work, on the one hand, we investigate the crystal structure evolution of titanium diboride and boron carbide composite ceramic on meso-level under strong impact loading condition. Also we study damage rules of titanium diboride and boron carbide and the relationship of each other; on the other hand, we simulate crystal structure evolution and bond valence of titanium diboride and boron carbide composite ceramic using crystal phase field theory of Density Functional Theory combined numerical simulation. Ultimately, this research reveals the relationship between the structure evolution and failure behaviors and provides foundation of structure design of high-performance boride ceramic.