Active media forming

Active media-based forming encompasses a variety of processes for shaping tubes, profiles, and sheets. Hydroforming (HF) of tubes and profiles is the most important technology in this group of processes. Both at room temperature, preferably with liquid active media, and at forming temperatures up to 1100 °C using gases, a wide range of materials can be shaped. In addition to the forming temperature, the strain rate is a process parameter to extend technological limits and areas of application. This is particularly true for superplastic forming, which is characterized by low strain rates that, combined with high forming temperatures, allow for forming degrees of several hundred percent.

Temperature also plays a significant role in some process variants. In addition to the classical active media-based hot forming of light metals, a process combination of hydroforming and press hardening has been realized at the Fraunhofer IWU. This approach combines the advantages of structural and material lightweight construction. With hydroforming-press hardening, ultra-high-strength structural components can be manufactured from closed profiles made of manganese-boron steels. Another application of hydroforming is its combination with injection molding in a single tool to produce hybrid components.

Trends

• Forming of a wide range of materials
• Forming temperatures from room temperature to over 1100 °C
• Expanding technological limits and applications through targeted use of strain rate and forming temperature as process parameters
• Economic production of components and assemblies through combination with or integration of other processes:
  • Heat treatments
  • Injection molding
  • Integration of joining operations