Occupant protection depends on efficient restraint systems and paddings on the one hand and on structural design of body components on the other.
An efficient compatibility design depends on the specific energy absorption and the force-crush-distance characteristic of the respective body components.
The mass-specific energy absorption of body components is based on the component design and on the material characteristics.
Once a highly efficient energy transformation has been achieved, further improvements of specific energy absorption can be obtained only by modifying such features as elasticity modulus, yield strength, yielding point, or weight for example.
Modern vehicle bodies are preferable made of ductile materials. Due to their low specific weight, plastics and aluminum have good prerequisites for an improved specific energy absorption, if the elastic and plastic deformation behaviour of both materials is left out of account for the present.
The present paper gives an idea of the usability and limits of aluminum sheet for application in energy absorbing body structures as compared to steel sheet.
The comparison shows that the specific energy absorption of aluminum sheets is at least 30% higher over wide ranges of real accident collisions. So, the use of aluminum sheets in combination with efficient restraint systems allows to improve the occupant protection without increasing the vehicle weight.
It must be qualified, however, that quite a number of specific problems related with aluminum have to be solved prior to introducing it into series production.