Forming based on active media

Active media-based forming comprises numerous processes for forming tubes, profiles and metal sheets. Hydroforming (HF) is the most significant technology of this process group. A wide range of materials can be formed either at room temperature, particularly with liquid media, or also at forming temperatures of up to 1,100°C by using gases. In addition to the forming temperature, the strain rate constitutes another process parameter for extending the technological limits and fields of application. This especially applies to superplastic forming. It is characterized by low strain rates – associated with high forming temperatures – which enable effective strains of several 100 per cent. In comparison, electromagnetic forming is a high speed process where the forming process takes place within microseconds.

Temperature also plays a decisive role in several HF process variants. In addition to conventional HF hot forming of light metals, Fraunhofer IWU has also realized a process combination of HF and press hardening. This approach combines the advantages of structural construction and lightweight material design. HF press hardening can be used to manufacture super high strength structural components from closed manganese-boron steel profiles. Another new application consists in the combination of HF and injection molding in one tool for manufacturing hybrid components.