Solid vs Shell: Bending Failure

 

A disaster in try-out predicted by solid simulation but not by shell

In this simulation of a crossmember made of high strength steel, the toolmaker felt safe after good results in a shell simulation. But in the real process, the part cracks all over the bending radius!

So what went wrong? In solid simulation we can see, that this material has a much too high load in the outer layers of the radiuses, while the neutral fiber is all right.

For brittle high strength steels, the cracked outside leads to a material weakening, so the crack propagates through the component.

That's why for forming of High Strength Steel, we always simulate:

  • Shell: First feasibility study with 15 min calculation time!
  • Solid: Final validation of the method. Better safe than sorry!