A special type of die forming using a high pressure Hydraulic fluid to press room temperature working material into a die Discovered by HOLMSTROEM, MARTIN There are three types of hydroforming: 1. Tube hydroforming 2. Sheet hydroforming 3. Explosive hydroforming Used when a complex shape is needed A section of cold-rolled steel tubing is placed in a closed die set A pressurized fluid is introduced into the ends of the tube The tube is reshaped to the confine of the cavity Involves forming of sheets with application of fluid pressure Metal blank is subjected to hydraulic counter pressure generated by punchs Required deformation takes place Note: Sheet hydroforming provides a work-hardening effect as the steel is forced against the blanks through fluid pressure. Used for large parts Generates the forming pressure by a simple explosion above the part which is immersed in water. 1. Outer skin with its extreme demand of surface and dimensional accuracy. quality 2. Longer outer skin parts for passenger cars, utility vehicles 3. Low capital cost. Fewer and simpler dies. 4. Better NHV (noise, vibration and harshness )factors. 5. Reduction in weight. 7. High process capability. 8. Reduction in cost of component. Steel (mild and harder steels) Stainless Steel Aluminum alloys Research continues to expand the capabilities of the hydroforming process Extraordinary Fewer Design Flexibility. Parts Less Assembly Less Weight. Lower Less Tooling Costs. Post-Processing Greater Integrity (pressure flows the metal into corners for greater precision rather than streching) Results compared to conventional steel body structure: 50% less weight 45% less parts (less tools, less assembly) 45% less welding seams Tighter tolerances Volvo Hydroformed Structure concept in Aluminum, (Schuler Hydroforming 1998) Slow cycle time Expensive equipment and lack of extensive knowledge base for process and tool design Requires new welding techniques for assembly. Hydroforming is an innovative forming process Hydroforming is becoming more popular (ie.automotive and aerospace industries) The advantages outweigh the limitations Material increase selection is broad and continues to Information can be found everywhere!