In punching operations, says Prof Hoffmann, miniaturisation of components is being progressed, which is leading to ever-smaller hole diameters down to sheet-thickness/hole-diameter ratios of < 1.

Another development step in sheet-metalworking is increasing process integration in the punching operations. "The press", explains Hoffmann, "is then just one station in the process chain. More and more machining steps are being integrated either internally or using peripheral units, such as welding, inscribing, extrusion-coating with plastic, assembling or washing."

In the case of large-sized sheet-metal parts for bodywork manufacture, says Hoffmann, "an increase in sheet-metal material types is observable towards high-strength and ultra-high-strength variants". Sheets used in cold metal-forming nowadays reach strengths of 1,200 MPa.

Prof Hoffmann has also noticed a rise in warm-formed parts in the structural category with strengths of up to 1,600 MPa. In Hoffmann's view, this necessitates "modular-structure forming tools made of stress-matched materials, so as to prevent wear and tear and premature tool failure".

Currently under development, too, are harmonised virtual CAE process chains, a highly automated feature enabling the simulation results for the forming process to be selectively utilised for designing the tools involved.

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