How to relate compressive strengths of multi-directional laminates to fundamental unidirectional material strength?

如何将多向层压板的抗压强度与基本单向材料强度联系起来？

• 批准号: 2738850
• 金额: --
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2738850
• 关键词: How; relate; compressive; strengths; multi

Over recent years, fibre-reinforced polymers (FRP) have demonstrated excellent in-plane tensile properties and are used in aerospace, automotive, and energy applications due to their significant weight reduction. However, in-plane compressive properties are 40% lower on average than that of tensile properties. The compressive performance of FRP hasn't been well understood due to the challenges of identifying the materials' true compressive strengths. Fundamental compressive tests of composites show inconsistency of results as fibre instability can lead to structural failure. Further research on the compressive performance of composites is required to utilize FRP materials in further applications. This research project is supported by EPSRC and contributes to the objectives of NextCOMP for the next generation of fibre-reinforced composites to develop novel composite materials that can endure higher compressive load-carrying capability. The development of composite compressive properties can lead to further industrial utilization of composites in compressive applications. A review of naturally occurring composite structures will be used to inspire new techniques to design and manufacture advanced composites with novel architecture.The aim of this PhD project is to improve the compressive performance of composite materials. - Experimental procedures must be reviewed and improved to obtain a higher compressive failure strain of FRP materials than those reported.- Development of finite element analysis (FEA) models to validate experimental results. The model results would be used to predict the compressive performance of FRP materials using different architectures.- Validate new architectures of composite materials to improve the in-plane compressive performance of composite structures.- Design, manufacture, test, and analyse complex hierarchical architecture that results in improved compressive properties of composite materials.The key objectives for this project can be summarised as follows: - Review the effects of stacking sequence to identify new techniques that can support longitudinally loaded fibres in compression.- Assess current compressive test methods to identify suitable experimental procedures for compressive failure within composite laminates. - Investigate methods for fibre stability in compression through the reduction of fibre misalignment.- Overwound / overbraid architectures to delay kink band initiation.- Use of pultruded rod architecture to embed into current laminate architecture. - Monitor uni-directional material stability and its improvement with the use of hybrid composites. The research would support the purpose of identifying and improving the compressive performance of uni-directional FRP materials. This would increase the use of FRP structures in further engineering applications, in particular the aerospace and civil engineering sector. The traditional materials used are expensive to transport and can cause further risks to employees. FRP structures would re-innovate the current structures to allow for the manufacturing of portable lightweight structures with improved corrosion resistance properties. The development of novel composite architectures from natural composite architectures and current compressive enduring structures will lead to identifying techniques to improve the compressive properties of FRP materials.

近年来，纤维增强聚合物(FRP)表现出优异的面内拉伸性能，并因其显著减轻重量而被用于航空航天、汽车和能源应用。然而，平面内压缩性能比拉伸性能平均低40%。由于识别材料的真实抗压强度的挑战，FRP的抗压性能还没有被很好地理解。复合材料的基本压缩试验显示结果不一致，因为纤维不稳定会导致结构失效。为了进一步利用FRP材料进行应用，需要对复合材料的压缩性能进行进一步的研究。这项研究项目得到了EPSRC的支持，并有助于实现NextCOMP下一代纤维增强复合材料的目标，即开发能够承受更高压缩承载能力的新型复合材料。复合材料压缩性能的发展可以进一步推动复合材料在压缩应用中的工业应用。通过对自然形成的复合材料结构的综述，将启发设计和制造具有新结构的先进复合材料的新技术。本博士项目的目的是提高复合材料的压缩性能。-必须审查和改进实验程序，以获得比报道的更高的FRP材料的压缩破坏应变。-开发有限元分析(FEA)模型以验证实验结果。模型结果将用于预测使用不同结构的玻璃钢材料的压缩性能。-验证复合材料的新结构，以改善复合材料结构的平面内压缩性能。-设计、制造、测试和分析复杂的分层结构，从而改善复合材料的压缩性能。该项目的主要目标可概括如下：-审查堆叠顺序的影响，以确定可以支持纵向加载纤维压缩的新技术。-评估当前的压缩测试方法，以确定复合材料层压板内压缩破坏的合适实验程序。-研究通过减少纤维错位来提高纤维压缩稳定性的方法。-采用卷绕/编织结构来延迟扭结带的形成。-使用拉伸杆结构嵌入当前的层压结构中。-监测单向材料稳定性及其使用混杂复合材料的改进。该研究将为识别和提高单向FRP材料的抗压性能提供依据。这将增加玻璃钢结构在进一步的工程应用中的使用，特别是在航空航天和土木工程部门。使用的传统材料运输成本很高，可能会给员工带来进一步的风险。玻璃钢结构将重新创新目前的结构，以允许制造具有更好的耐腐蚀性的便携式轻质结构。在天然复合建筑和现有耐压结构的基础上发展新型复合建筑，将导致寻找提高FRP材料压缩性能的技术。