OPTIMIZATION OF AUTOMOTIVE COMPOSITE BUMPER BEAM WITH OPEN SECTION FOR PRODUCTION AND STRUCTURAL PERFORMANCE

Reduction of fuel consumption, satisfaction of current regulation and in particular the legislation regarding GHG emission and customer safety requirements are the main concerns of today for automotive industries. The effective means to address these issues are mainly based on the possibility of reducing the vehicle mass. In this perspective it is very promising to substitute the traditional steel by lightweight composite material. However, as the mechanical and failure behavior of composite materials are completely different from those characteristic for the traditional metallic material, substitution has to be made by a complete re-design. Beside to take advantage from the specific characteristic of the composite materials, re-design must take in great consideration both production technology and joining feasibility. Die forming manufacturing technology has been considered for the production technique due to its capability to produce open composite shells with the desired shape and to obtain structurally integrated crash box and bumper beam as a single component. Since open section beams are structurally weaker than similar closed section solutions for the intended loading case, besides cross overall sectional geometry optimization, different set of reinforcing ribs have been used to optimize the structural performance. The result shows that with a proper selection of reinforcing ribs, an open section beam can yield a structural performance comparable with that of the close section one.