CMMI-EPSRC: Damage Tolerant 3D micro-architectured brittle materials

CMMI-EPSRC：耐损伤 3D 微结构脆性材料

• 批准号: EP/Y032489/1
• 负责人: Vikram Deshpande
• 金额: $ 53.39万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY032489%2F1
• 关键词: CMMI; EPSRC; Damage; Tolerant; 3D

The search for materials that are lightweight and can withstand extreme service conditions has been a major driving force for material development in recent decades. Ceramic materials, while stable at high temperatures and in harsh environments, are limited in their structural applications due to their inherent brittleness and low damage tolerance compared to their metallic materials. An emerging class of materials referred to as micro-architectured materials offer a potential breakthrough to overcome this limitation. Our preliminary experimental results suggest that large-scale 3D micro-architectured materials, even when made from linear elastic brittle parent materials at scales that resemble bulk materials can exhibit extreme damage tolerance. Thus, in this project we propose to develop a deeper understanding of fracture and damage tolerance in a wide variety of micro-architectured materials made from (ceramic/ceramic-like) purely brittle parent materials. Our proposed research is based on two underlying hypotheses: (1) The discrete nature of the 3D micro-architectures either inherently gives rise to crack-bridging, introduces local anisotropy in the fracture toughness or both that leads to the observed extreme damage tolerance of micro-architectured materials made of inherently brittle parent materials. (2) The topological stochasticity in the 3D micro-architectures made of inherently brittle parent materials will result in diffused damage zones and enhanced crack-bridging, leading to further increase in damage tolerance. The specific objectives of our proposal are twofold. First, ascertain the crack growth and damage tolerance mechanisms of large-scale 3D periodic micro-architectures made of linear elastic brittle parent materials. Second, extend the mechanistic understanding of fracture in periodic micro-architectures to stochastic micro-architectures made of brittle ceramic parent materials. This will enable us to test our hypotheses and address several fundamental questions of technological relevance that are raised in this proposal. Our proposed education and outreach plans are also fully integrated with the research plan through a common focus on mechanics of micro-architectured materials.Classical fracture mechanics has been a highly successful theory for analyzing fracture of continuum materials. However, our preliminary results indicate that these concepts do not directly extend to discrete 3D micro-architectured materials, even those made of purely linear-elastic brittle parent materials. In particular, the discreteness of the microstructure renders standard measures of fracture properties and fracture testing protocols inadequate. This project will expand upon the traditional understanding of classical fracture mechanics and associated testing protocols by developing a comprehensive mechanistic understanding of damage tolerance and devising a novel methodology to characterize fracture response of a wide variety of 3D micro-architectured materials made from purely brittle materials. Furthermore, by gaining a deeper understanding of the correlation between micro-architecture and fracture response, we will create fracture mechanism and performance maps that can be used for selecting an optimum micro-architecture based on parameters such as size and density of the structure and loading conditions. The project's main impact lies in the development of a methodology that will enable the discovery, design, and development of lightweight, damage-tolerant micro-architectured materials for extreme loading conditions. These materials have potential uses not only in structural applications but also in relevant contemporary technologies such as energy, biomedical and micromechanical devices. This project will facilitate damage tolerance and structural integrity analysis for reliable use of micro-architectured materials in these highly sought-after technologies.

近几十年来，寻找轻巧且可以承受极端服务条件的材料一直是材料开发的主要驱动力。陶瓷材料虽然在高温和恶劣的环境中稳定，但由于其固有的脆性和与金属材料相比，其结构应用受到限制。一类新兴的材料称为微实验室材料，为克服这一限制提供了潜在的突破。我们的初步实验结果表明，即使用线性弹性脆性父材料制成的大规模3D微构造材料，类似于散装材料的尺度上也可以表现出极端的损害耐受性。因此，在这个项目中，我们建议在通过（陶瓷/陶瓷样）纯粹的脆性父母材料制成的多种微构造材料中对断裂和损伤的耐受性有更深入的了解。我们提出的研究基于两个基本的假设：（1）3D微体系结构的离散性质固有地产生了裂纹，在裂缝韧性中引入了局部各向异性，或者两者都会导致观察到的固有固定材料的极度损害材料由固有的脆性脆性父母材料产生的极度损害。 （2）由固有的脆性材料制成的3D微构造中的拓扑随机性将导致扩散的损伤区域和增强的裂纹桥梁，从而进一步增加损害耐受性。我们提案的具体目标是双重的。首先，确定由线性弹性脆性母体材料制成的大规模3D周期性微体系结构的裂纹生长和损伤耐受性机制。其次，将周期性微构造中断裂的机械理解扩展到由脆性陶瓷母体材料制成的随机微体系结构。这将使我们能够检验我们的假设，并解决该提案中提出的技术相关性的几个基本问​​题。我们提出的教育和外展计划还通过对微实验室材料的机制的共同关注进行了与研究计划的完全融合。古典断裂力学一直是分析连续材料断裂的非常成功的理论。但是，我们的初步结果表明，这些概念并未直接扩展到离散的3D微构造材料，即使是由纯线性弹性脆性父材料制成的材料。特别是，微观结构的离散性使断裂特性和断裂测试方案的标准度量不足。该项目将通过对损害耐受性的全面理解并设计一种新颖的方法来表征各种纯属脆性材料制成的各种3D微实验室的材料的裂缝反应来扩展对经典断裂力学和相关测试方案的传统理解。此外，通过对微体系结构与断裂响应之间的相关性有更深入的了解，我们将创建断裂机制和性能图，可用于根据参数（例如结构和负载条件的大小和密度）选择最佳的微体系结构。该项目的主要影响在于开发一种方法，该方法将使能够发现和开发轻巧，耐受损害的微体系结构材料，以实现极端负载条件。这些材料不仅具有在结构应用中的潜在用途，而且还具有相关的当代技术，例如能源，生物医学和微机械设备。该项目将促进损伤的耐受性和结构完整性分析，以在这些备受追捧的技术中可靠地使用微构造材料。