Design, processing, and characterization of interlaminar response of a multi-layer carbon - Epoxy prepreg

Single lamina prepregs are the most commonly used materials in the manufacturing of advanced composite structures. Conventionally, these prepregs are made using a semi-cured single layered composite. For thermoset resins, single layer prepregs are usually stored in the refrigerator and final laminated structure is formed by laying several single layer prepregs at various ply orientations. This manufacturing process involves a labor-intensive debulking process. The major reason for the use of single layer prepreg is to ensure the flexibility so that they can be draped properly in a complex mold. In many application, composite manufacturers use a specific number of layers for the manufacturing of specific part and the flexibility may not be a very important factor, especially for flat parts. In the current article possibility of manufacturing multilayer prepreg is investigated. The multi-layer prepreg is manufactured using Epon862-W and regular woven carbon fiber fabric in a semi-closed mold by using a hot press. The performance, in terms of delamination resistance, of the structures made from the single layer prepregs and a multi-layer prepreg, has been investigated. The progressive failure features are also characterized from the micrographs of the fractured surfaces.