Non-Destructive Impact Damage Detection on Carbon Fiber Reinforced PlasticsIDD-Metro within BRAGECRIM

使用轻质碳纤维增强塑料（CFRP）减轻产品重量是该行业节约能源、应对国际气候目标和不断增加的能源成本的一个推动因素。CFRP的特点是高比刚度和强度，这使它们成为航空工业、风力涡轮机、汽车工业甚至消费品工业中轻量化应用的理想选择。事实上，最近已经推出了新的电动汽车，考虑到支撑结构中的大量CFRP，从而减轻了重量并增强了驾驶动力。由于CFRP的使用从小批量生产扩展到大批量生产，预计CFRP的需求在未来几年将增长。CFRP产品的经济可行性必须在整个产品生命周期中得到保证。因此，必须确保长期运行的可靠性和经济的维修过程。飞机和航空航天工业的既定概念基于手动过程，并且通常需要更换损坏的部件。CFRP产品的大规模生产需要经济可行且高效的修复工艺。因此，需要无损、可靠、高效和自动化的测量技术来满足材料、部件和维修车间的特定要求。便携式无损检测方法的发展是不可避免的，它可以可靠地和全面地检测缺陷。热成像技术非常适合于CFRP缺陷的无损检测。热成像系统是便携式的，覆盖大面积，并且具有时间效率。热成像基于2D图像。这些图像包含样本不同层的叠加（深度信息）。但是，不能直接获得部件上缺陷的绝对位置和尺寸及其深度信息。该项目的目标是设计、开发和设置一个系统，以可靠地检测CFRP部件中的冲击损伤及其各自的特性（尺寸、形状、位置和深度），从而在车间环境中实现可靠的修复过程。这一目标将通过增强热成像来实现，以检测碳纤维增强塑料中缺陷的3D特性。对不同冲击缺陷的CFRP试件进行了热像、剪切像和CT研究。根据CT结果，考虑缺陷的深度和几何形状以及损坏的严重程度等属性，将绘制缺陷分类。融合上述测量技术的结果，将创建一个评估模型。该模型将被集成到一个演示和验证。该项目的额外好处是用于热成像和CT的测量策略，以更好地量化CFRP损伤。结果将提高CFRP的质量保证，并将使可靠的维修过程。该模型可以推广到其他材料和缺陷。

The reduction of weight of products using lightweight carbon-fibre-reinforced plastics (CFRP) is an enabler for the industry to save energy and face the international climate objectives and increasing energy costs. CFRP are characterized by a high specific stiffness and strength, which make them ideal for lightweight applications in e.g. aviation industry, wind turbines, automotive industry and even consumer goods industry. In fact, new electric vehicles have been introduced recently considering a significant amount of CFRP in the support structure, thus reducing weight and enhancing driving dynamics. The demand of CFRP is expected to grow in the coming years, since the use of CFRP expands from small batch production to mass production. The economic feasibility of CFRP products must be assured throughout the whole product life cycle. Therefore, the long term operational reliability and economic repair processes must be assured. The established concepts from aircraft and aerospace industry base upon manual processes and in general demand a replacement of damaged parts. A mass production of CFRP products requires economically feasible and efficient repair processes. Therefore, non-destructive, reliable, efficient and automated measurement technology is required to fit the material, component and repair work shop specific requirements. The development of portable and non-destructive testing methods, which reliably and holistically detect defects, is inevitable. Thermography is well suited for the non-destructive detection of defects in CFRP. Thermography systems are portable, cover large areas and are time efficient. The thermography is based on 2D images. These images contain an overlay of the different layers of the sample (depth information). But, the absolute position and size of the defect on the component and its depth information are not directly accessible. The objective of this project is to design, develop and setup a system to reliably detect impact damages with their respective properties (size, shape, position and depth) in CFRP components that enables a reliable repair process in the workshop environment. This goal will be achieved by enhancing the thermography to detect those 3D properties of defects in carbon fiber-reinforced plastics. CFRP samples with different impact defects will be studied with thermography, shearography and CT. From the CT results, a defect classification will be drawn, considering properties like the depth and geometry of the defects and the severity of the damage. Fusing the results from aforementioned measuring techniques, an evaluation model will be created. The model will be integrated into a demonstrator and validated. The additional benefits from this project are measurement strategies for thermography and CT to better quantify the CFRP damages. The results will improve the quality assurance of CFRP and will enable reliable repair processes. The model can be extended to other materials and defects.