Hybrix material and its Crash Performance

One of the major challenges for the automakers is to improve the driving performance by enhancing the weight balance between front and rear compartment of the vehi-cle. The task is not so straight for-ward due to the natural location of the engine compartment and the powertrain. One common solution is to reduce the weight of the adja-cent components, e.g., bonnet, wheel drive system, chassis com-ponents, battery, etc.. Therefore, using advanced and innovative materials are almost essential for automaker. 

The leading car manufacturers, Volvo Cars, with automobile safety strategy as the first point of its development agenda, has taken initiative to apply new materials to enhance the common weight balance issue and im-prove the pedestrian safety in a frontal colli-sion scenario. In order to verify the perfor-mance of the new material, the project team has decided to purchase and build beam sec-tions of three selected materials sharing the same geometry to perform impact tests in Volvo’s drop tower facility. 

Based on an extensive literature study two potential material structures namely, Carbon Fiber Reinforced Polymer (CFRP), and Hy-brix™ micro-sandwich material beside alumi-num as a reference material were selected. The target materials were found to be appro-priate regarding impact resistance and flexur-al stiffness with the focus on reducing the weight, while meeting important demands on the bonnet safety feature. 

The results from the investigation confirm that the CFRP beam with inside PVC foam ab-sorbed least amount of energy at the impact test and it was only located in the elastic re-gion of the material. This indicates that the structure did not have the ability to plastic deformation which is an important require-ment for the proposed application. However, it is possible to reduce the total weight up to 24% lighter than the reference material. 

The Hybrix™ material with temper-rolled stainless steel grade as face materials, ab-sorbed most amount of energy with almost 23% higher energy absorption capability. It is almost a parallel upward shift of the reference material’s energy absorption curve. However, the structural beam with Hybrix™ design to-gether with existing configuration was 27% heavier than the aluminum material. 

While there is no question that, specific anal-yses are needed for the bonnet with A Well Weight Optimized Hybrix™ configuration.