Papers by Keyword: FML

Abstract: Fiber-metal-laminates (FML) provide excellent fatigue behavior, damage tolerant properties, and inherent corrosion resistance.To speed up manufacturing and simultaneously increase the geometrical complexity of the produced FML parts, Mennecart et al. proposed a new single-step process combining deep-drawing with infiltration (HY-LCM). Although the first experimental results are promising, the process involves several challenges, mainly originating from the Fluid-Structure-Interaction (FSI) between deep-drawing and infiltration. This work aims to investigate those challenges to comprehend the underlying mechanisms. A new close-to-process test setup is proposed on the experimental side, combining deep-drawing of a hybrid stack with a linear infiltration. A process simulation model for FMLs is presented on the numerical side, enabling a prediction of the dry molding forces, local Fiber Volume Content (FVC) within the three glass fiber (GF) interlayers, and simultaneous fluid progression. The numerical results show that the local deformation of the hybrid stack and required forces are predictable. Furthermore, lateral sealing of the hybrid stacks leads to deviations from the intended initially one-dimensional fluid progression. Eventually, the numerical results demonstrate that most flow resistance originates from geometrically critical locations. Future experimental and numerical work will combine these insights to focus on the flow evaluation during deformation and a successful part-level application.

Abstract: The formability of fiber-metal laminates (FML) produced in autoclave process is limited due to processing restrictions. In addition, the industrial application of these hybrid laminates is usually unattractive, as the production time leads to high production costs. A new manufacturing process has been developed, which combines the deep-drawing process with a thermoplastic resin transfer molding process (T-RTM). Three-dimensional sandwich components were produced. They consist of 1 mm DC04 steel face sheets and a varying number of intermediate layers of thermoplastic reinforced glass fiber fabrics. Due to the manufacturing process, the mechanical properties differ locally depending on the location-dependent degree of sheet metal forming and the location-dependent fiber draping. The mechanical properties are therefore investigated by three-point flexural tests on miniaturized samples in order to map these location-dependent properties.

Abstract: According to the finite element method, this article has established the FML’s finite element model. By comparing to the test data and studying of the tensile behavior of FML, it has verified valid of the model. When the aluminum layer yields under the tensile load, the composite layer has the most tensile load. And the model has been developed to predict the stability influenced by the rib’s height.

Abstract: Carbon Fiber (CF)/Metallic Alloy (MA) laminar structures, also known as Fiber Metal Laminates (FML) allow diminishing the airship weight. Because of that the use of these materials is growing continuously in the aerospace industry. These composites materials need to be drilled because of the assembly requirements in the different airship elements. The most common problems that can appeared when those structures are machined are related with the interaction of the tool with dissimilar materials, which need different cutting parameters for the optimized machining process. This work reports on the results about a study of the dry drilling processes of hybrid composites Carbon Fiber/aluminum alloy, and especially CF/AA2024.