This reduces costly iteration cycles and thereby shortens the entire development and manufacturing process. What is more, the concept can also be applied to areas where Integrative Simulation was previously too expensive or time-consuming.
Short-fiber-reinforced thermoplastic injection molded parts are increasingly being used in place of steel or aluminum. The Fraunhofer Institute for Structural Durability and System Reliability LBF has developed a method to take into account the fiber orientation of short-fiber-reinforced injection molded parts, even at stages where there are still no components, such as prototypes. This phenomenological calculation concept is expected to close a significant gap in the design cycle of these molded parts.
Depending on the level of detail required, the new procedure can be regarded as an independent solution for component design or as an upstream supplement for integrative simulation.
Typical applications for short-fiber-reinforced thermoplastic injection molded parts include their usage in the automotive or aerospace industries. In the automotive industry, in particular, where large quantities are required in the shortest time frames, the injection molding process represents an efficient manufacturing process of plastics, also allowing for high design flexibility. However, predicting fiber orientation which is determined by the process, material and dimensions being used, still presents a major challenge. This concept is still at the cutting edge of current research.
One method of incorporating fiber orientation into the design of corresponding shaped parts is integrative simulation. This makes it possible to transfer relevant process information into an associated structure simulation using a suitable interface and therefore predict component behavior. However, the individual steps of integrative simulation must all be consistently validated and calibrated using experimental data. This means that process parameters and tool geometries must be known and real moldings must be available. Consequently, this concept is only available as of the stage of component development where prototypes can already be produced.
By contrast, the process developed by researchers at Fraunhofer LBF already takes the fiber orientation of short-fiber-reinforced injection molded parts into account at a stage where no actual components are yet available. Unlike with fully integrative approaches, the new calculation method does not determine the fiber orientation based on finite elements but rather on shaped elements or key areas. These can be, for example, ribs, domes or flat areas.
COMPAMED-tradefair.com; Source: Fraunhofer Institute for Structural Durability and System Reliability LBF