Damage analysis of fabric-reinforced polymer composites under superimposed in-plane/out-of-plane stress conditions

面内/面外叠加应力条件下织物增强聚合物复合材料的损伤分析

基本信息

批准号：
269649711
负责人：
Professor Dr.-Ing. Maik Gude
金额：
--
依托单位：
Institut für Leichtbau und Kunststofftechnik
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2015
资助国家：
德国
起止时间：
2014-12-31 至 2017-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/269649711?language=en
关键词：
Damage analysis fabric reinforced polymer

项目摘要

The objective of the project is the development of appropriate test methods for strength analysis of fabric-reinforced polymers (FRP) under superimposed in-plane/out-of-plane-stress states as basis for the reliable design of highly stressed lightweight structures. Superimposed states of stress are characteristic for load application areas of FRP components such as fan blades or profiled drive shafts, and they mainly consist of in-plane tension or shear stresses and through-thickness compressive stresses. Currently, for dimensioning of load application areas, there are no reliable material parameters and no suitable failure criteria which take account of stress interactions and of the influence of the specific fabric architecture to material failure. Hence, the focused materials of the investigations are carbon-fibre-reinforced thermosets with different configurations of the plain-weave fabric reinforcement. Main objectives are experimental and numerical studies on the impact on material strengths of the characteristic fabric architecture with the fibre undulation accompanied by the interlocking of adjacent fabric layers.Appropriate specimen designs for inducing in-plane tension/through-thickness compression or shear/through-thickness compression stress states will be refined and developed, respectively, by using finite element method (FEM). Main focus will be on the one hand on the selection of suitable geometric parameters to reduce unwanted stress peakes and on the other hand on diminishing frictional influences concerning the compression load transfer area at the compression dies. Necessary for the experimental tests are specimens with a sufficiently large thickness and reproducible quality. Manufacturing of such specimens will be performed with a resin transfer molding process, which is adapted regarding temperature control and curing. After that, the real fabric architecture within the compacted and consolidated laminates will be analysed and documented by means of computed tomography (CT). Experimental material tests with different load paths are performed using a servohydraulic planar biaxial testing machine with four actuators. To describe the experimentally determined fracture phenomena and the fracture processes, the fracture surfaces of the specimens will be analysed and characterised by microscopy. In addition to the experimental tests, virtual tests with FEM will be carried out on representative volume elements with fabric reinforcements. For that, the collected data from CT analyses concerning the compacted fabric architecture are implemented within the finite element model.Based on the experimental and numerical outcomes on the failure chronology and the fracture modes in the combined stress states, suitable approaches for the description of material failure especially considering the specific fabric architecture will be developed.

该项目的目的是开发适当的测试方法，用于在叠加的面内/平面内压力态下对织物增强聚合物（FRP）的强度分析，以此作为可靠设计高应力的轻质结构的可靠设计的基础。压力叠加的状态是FRP组件的负载应用区域（例如风扇叶片或配置式驱动轴）的特征，它们主要由平面张力或剪切应力以及透明的压缩应力组成。当前，对于负载应用领域的尺寸，没有可靠的材料参数，也没有合适的故障标准，这些标准考虑了压力相互作用以及特定织物架构对材料故障的影响。因此，研究的重点材料是碳纤维增强的热固性，并具有不同的织物织物增强型的构型。主要目标是对特征织物结构对材料强度的影响的实验和数值研究，并伴随着相邻织物层的互锁。适当的标本设计用于诱导平面张力/贯穿厚度的压缩或剪切/剪切/剪切/透明压缩应力状态，将分别使用和开发的元素（使用有限的元素）。一方面，主要的焦点将是选择合适的几何参数，以减少不需要的应力峰，另一方面，关于压缩模具处压缩负荷转移区域的摩擦影响减少。实验测试所需的是具有足够厚度和可重现质量的标本。此类标本的制造将通过树脂转移成型过程进行，该过程适用于温度控制和固化。之后，将通过计算机断层扫描（CT）对压实和合并层压板中的真正织物结构进行分析和记录。具有不同载荷路径的实验材料测试是使用带有四个执行器的伺服液压平面双轴测试机进行的。为了描述实验确定的断裂现象和断裂过程，将通过显微镜分析标本的断裂表面。除了实验测试外，还将对具有FEM的虚拟测试对带有织物增援的代表性元素进行。为此，在有限元模型中实现了有关压实织物结构的CT分析的数据。基于对故障年代的实验和数值结果，以及合并应力状态中的断裂模式，合适的方法，用于描述材料失败的描述，特别是考虑到特定织物结构的描述。