Understanding and Improving Ceramic Armour Materials

了解和改进陶瓷铠装材料

• 批准号: EP/G042675/1
• 负责人: Jon Binner
• 金额: $ 51.98万
• 依托单位: Loughborough University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FG042675%2F1
• 关键词: Understanding; Improving; Ceramic; Armour; Materials

Ceramic materials are used for both personnel and vehicle armour since they can be very effective at stopping ballistic projectiles by breaking and eroding them. However, such armour is generically fairly heavy and does not have multihit capability due to its fragmentation during impact. The development of new ceramics for armour is further hindered by the limited understanding of the mechanisms involved in their success and therefore what the characteristics of the ideal ceramic should be. Challenges to improving the situation include: the difficulties in defining initial material state (defects and damage); experimental characterisation of short-lived impact events; the fragmented nature of the specimens left behind; and the importance of the whole system to the dynamic failure process (e.g. impact resistance depends inherently on the shape and size of the component unlike conventional materials properties). This hinders the comparison of reports of competing materials from different labs. Previous work has included the use of a range of mechanical testing equipment (from quasi-static, low velocity hydraulic and gas gun actuated split- and direct-impact Hopkinson bar systems to intermediate-, high- and hyper-velocity gas and powder guns) and aimed to quantify the impact response by means of high-speed photography. There have also been attempts to simulate experiments using a range of modelling techniques. However, most of the available literature uses particular techniques and materials in isolation. No work has yet demonstrated the use of an integrated experimental-numerical, multi-scale approach to understanding and predictively modelling deformation and fracture of ceramics subject to impact loading.A holistic approach to developing an understanding of the high strain rate performance of ceramics is proposed. Modelling plays a dual role, which is both to design the experiments employed to understand the materials' behaviour on a macroscopic scale and to give insight into the role of micromechanisms in determining ballistic performance. Model input will be provided by materials property data determined before testing (e.g. basic information such as grain size and hardness and detailed surface and subsurface characterisation of the defect population using advanced microscopy). The models will be developed by comparing their predictions with the output of instrumented laboratory tests covering a wide range of strain rates (10 exp -4 to 10 exp 6 /s), ballistic tests (through DSTL) and with the results of novel post mortem characterisation. The latter will include detailed characterisation of the fragments ejected from the surface and the remnants of the main specimen. This will include assessments of fracture mode and origin using SEM, dislocations and twinning by TEM, particle size distributions by laser scattering and the use of optical luminescence microscopy for the first time in this context to measure residual stresses in the specimens with a spatial resolution of 2um and to measure dislocation densities. This quantitative information can be compared directly with the predictions of the models. This approach will be used on a range of ceramics with systematically differing characteristics and will give comparative information about which microstructural features and mechanical properties successful ceramics possess, as well as enabling the development of a fundamental understanding of the high strain rate performance. The materials used will include both existing armour ceramics and, for the first time, novel nano-grained and nano-composite ceramics which quasi-static tests indicate to have interesting properties for armour applications (e.g. the ability to undergo much more plastic deformation before crack initiation). The outcome will be the ability to design ceramic microstructures and armour systems with improved performance. The final task will be to begin making such structures.

陶瓷材料被用于人员和车辆装甲，因为它们可以通过破坏和侵蚀来非常有效地阻止弹道弹丸。然而，这种装甲通常相当重，并且由于在撞击过程中破碎而没有多重命中能力。由于对其成功的机制的理解有限，因此对理想陶瓷的特性应该是什么，进一步阻碍了新型装甲陶瓷的发展。改善这种状况的挑战包括：难以定义材料的初始状态（缺陷和损伤）；短期撞击事件的实验表征；遗留下来的标本支离破碎；以及整个系统对动态失效过程的重要性（例如，与传统材料性能不同，抗冲击性本质上取决于部件的形状和尺寸）。这阻碍了对来自不同实验室的竞争性材料的报告进行比较。之前的工作包括使用一系列机械测试设备（从准静态、低速液压和气枪驱动的劈裂和直接冲击霍普金森杆系统到中速、高速和超高速气枪和火药枪），旨在通过高速摄影来量化冲击响应。也有人尝试使用一系列建模技术来模拟实验。然而，大多数现有文献孤立地使用特定的技术和材料。目前还没有工作证明使用综合实验-数值，多尺度方法来理解和预测陶瓷在冲击载荷下的变形和断裂。提出了一种全面的方法来发展对陶瓷高应变率性能的理解。建模起着双重作用，既可以设计实验，以了解材料在宏观尺度上的行为，也可以深入了解微观机制在确定弹道性能中的作用。模型输入将由测试前确定的材料性能数据提供（例如，诸如晶粒尺寸和硬度等基本信息，以及使用高级显微镜对缺陷种群的详细表面和表面下特征）。这些模型将通过将其预测结果与仪器实验室测试的输出结果进行比较来开发，这些测试涵盖了广泛的应变速率（10 exp -4至10 exp 6 /s）、弹道测试（通过DSTL）以及新的死后表征结果。后者将包括从表面喷出的碎片和主要标本残余物的详细特征。这将包括使用扫描电镜评估断裂模式和起源，通过透射电镜评估位错和孪生，通过激光散射评估粒度分布，并在此背景下首次使用光学发光显微镜以2um的空间分辨率测量样品中的残余应力并测量位错密度。这些定量信息可以直接与模型的预测进行比较。这种方法将用于一系列具有系统不同特性的陶瓷，并将提供有关成功陶瓷具有的微观结构特征和机械性能的比较信息，以及使对高应变率性能的基本理解得以发展。所使用的材料将包括现有的装甲陶瓷，以及首次使用的新型纳米颗粒和纳米复合陶瓷，准静态测试表明，这些陶瓷在装甲应用中具有有趣的性能（例如，在裂纹萌生之前能够承受更多的塑性变形）。其结果将是能够设计出具有改进性能的陶瓷微结构和装甲系统。最后的任务将是开始制作这样的结构。

项目成果

A new method for the generation of arbitrarily shaped 3D random polycrystalline domains

• DOI: 10.1007/s00466-014-1068-3
• 发表时间: 2014-12
• 期刊: Computational Mechanics
• 影响因子: 4.1
• 作者: S. Falco;P. Siegkas;E. Barbieri;N. Petrinic

Bullet Proof

防弹

• 发表时间: 2013
• 期刊: Materials World
• 作者: Binner J

Quantitative analysis of the residual stress and dislocation density distributions around indentations in alumina and zirconia toughened alumina (ZTA) ceramics

• DOI: 10.1016/j.jeurceramsoc.2013.09.021
• 发表时间: 2014-03-01
• 期刊: JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
• 影响因子: 5.7
• 作者: Huang, S.;Binner, J. G. P.;Todd, R. I.
• 通讯作者: Todd, R. I.

Characterisation of damage mechanisms in oxide ceramics indented at dynamic and quasi-static strain rates

动态和准静态应变率下压痕氧化物陶瓷损伤机制的表征

• DOI: 10.1016/j.jeurceramsoc.2019.06.054
• 发表时间: 2019
• 期刊: Journal of the European Ceramic Society
• 影响因子: 5.7
• 作者: Dancer C

Developments in Strategic Materials and Computational Design III

战略材料和计算设计的发展 III

• DOI: 10.1002/9781118217542.ch9
• 发表时间: 2012
• 作者: Falco S