To meet the growing demand for rapid, low-cost die fabrication technology in the sheet metal forming industry, easy-to-machine, polyurethane-based, composite board stock is widely used as a rapid tooling material. However, the failure mechanisms of the rapid prototyped tools are not clearly understood, thus making the prediction of tool life difficult. As a fundamental step for effective tool life estimation, the microstructure and the mechanical properties of the polymer composite tooling material were characterized. A finite element model of 90° V-die bending process was developed, and the effects of process parameters on stress distribution in punch and die were investigated through simulation. The simulation results were verified through experiments using instrumented, laboratory-scale punch and die sets.

Issue Section:
Technical Papers
Keywords:
fatigue, bending, finite element analysis, friction, fracture, forging, metals, forming processes, stress-strain relations, tensile strength, crystal microstructure
Topics:
Finite element model, Fracture (Materials), Polymer composites, Sheet metal work, Stress, Tooling, Fatigue, Mechanical properties, Cycles, Shapes, Fatigue failure, Friction, Finite element analysis, Urethane elastomers
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