多尺度颗粒陶瓷材料的抗侵彻机理研究

Damage theory of brittle ceramics which is penetrated by the high speed projectile has become the key technical bottleneck in the design and development of ceramic armor. In the contact region of the projectile, the ceramic target which is impacted by the strong confinement and inertial effect has actually been damaged to be granular. However, granular ceramic is a multiscale and complex system, which is a challenging problem to study the dynamic mechanical property and anti-penetration mechanism. In order to establish the causation in relationship between microscopic properties and macro mechanical response of granular ceramic, the present project is carried out by the following aspects: (1) The loading, testing and recovery system of plate impact experiment is designed to aquire the granular ceramic which is approach to the penetration conditions. And the effect of shock pressure is studied in the analysis of micromorphology and size distribution of powders. (2) Under different loading strain rates conditions, the ratio of particle breakage is quantified. Then the theoretical model which is consists of the external work and relative of particle breakage ratio is established in order to obtain the influence mechanism of particle breakage of strain rates effect. (3) The influence mechanism of micromorphology and size distribution of powders is aquired in the bllastic performance study of ceramic armor. The mass erosion law of the projectile is gained at different impact velocities in order to evaluate the contribution of ballistic effectiveness in the penetration of composite targets. The achievement of the project is expected to enrich the theory of interaction mechanism between target and projectile, and to provide reliable theory basis and technical support in the design of armor protection.

脆性陶瓷受弹丸高速侵彻下的损伤理论已成为制约陶瓷装甲设计与发展的关键技术瓶颈。受强约束和惯性效应的影响，弹丸接触区域的陶瓷靶实际已完全损伤至颗粒状，然而颗粒陶瓷是一个多尺度复杂体系，其动态力学性能及抗侵彻机理研究是富有挑战性的课题。为建立颗粒陶瓷微观特性与宏观力学响应之间的关系，本项目将针对以下问题展开研究：（1）设计平板撞击试验加载、测试和回收系统以获取近侵彻条件下的颗粒状陶瓷材料，分析冲击压力对颗粒微观形态和粒度分布的影响。（2）量化不同应变率加载条件下的颗粒破碎率，建立颗粒陶瓷外力功和相对破碎率之间理论模型，揭示颗粒破碎对应变率效应的影响机理。（3）获得颗粒微观形态和尺寸对装甲抗弹性能的影响机制，明确弹丸不同撞击速度下的质量侵蚀规律，评估颗粒陶瓷层对复合装甲抗弹效益的贡献。通过以上问题研究将进一步完善陶瓷装甲弹靶作用机理的理论基础，并为装甲防护设计提供可靠的理论依据和技术支持。

多尺度颗粒陶瓷材料的动态力学性能及其抗侵彻机理研究是陶瓷复合装甲研究领域中富有挑战性的课题。为解决这一难题，本项目采用试验、理论和数值仿真相结合的方法，针对一维应力和平面冲击波加载下完整陶瓷材料的失效与破碎特性、颗粒陶瓷材料动态力学响应及其抗侵彻特性等问题展开了详细研究，具体可细分为五部分内容。第一，采用单脉冲SHPB加载装置完成了对脆性陶瓷一维应力波加载试验，获得了材料强度的应变率效应，通过SEM扫描分析了材料的微观断裂机制及其对宏观力学性能的影响；修正了DID模型，完成了对回收颗粒试样的粒度分析。第二，设计了平板撞击试验，预埋自制PVDF完成了对平面冲击波的测量，获得了不同冲击压力下试样的破碎粒度分布，并从微观角度分析了颗粒断裂模式、剪切滑移、局部塑性等特征。第三，开展了不同粒度和级配的颗粒陶瓷材料的SHPB单脉冲加载试验，对材料强度、环向应力、轴向应力、静水压力等变量的应变率效应进行了研究，并分析了试样应力应变关系；引入Hardin相对破碎率，量化了不同粒度和级配下颗粒破碎随加载压力的变化规律。第四，采用火药枪发射装置，完成了对颗粒陶瓷材料复合装甲的抗侵彻机理研究，针对含不同粒度和级配颗粒的靶板变形进行了详细分析，包括面板开孔、侵彻深度以及背板变形等。最后，通过LS-DYNA软件完成了对弹丸高速复合装甲的数值仿真分析，对侵彻过程中的颗粒陶瓷失效与破碎、靶板应力波传播、弹丸速度和加速度等进行了详细分析，发现复合装甲抗侵彻性能随着颗粒粒度的减小逐渐增大，含单尺寸颗粒的靶板相较不同级配颗粒下的靶板具有更优的抗弹性能，但不同级配下颗粒陶瓷靶内材料在几何空间具有不均匀性，从而导致弹丸偏转更为严重。总之，通过对以上问题的研究，可进一步完善陶瓷装甲弹靶作用机理的理论基础，并为装甲防护设计提供可靠的理论依据和技术支持。