NEW MATERIALS AND CONSTRUCTION METHODS FOR MULTI-MATERIAL-DESIGN, LIGHTWEIGHT CONSTRUCTION AND MODULARITY IN FUTURE VEHICLE CONCEPTS

摘要

Besides reducing fuel consumption, the chief motivating factor behind the development of new vehicle structures is the desire to decrease climate-affecting emissions. One approach to addressing this involves reducing the vehicle mass and, as such, the various strategies relating to lightweight construction. Various methods of lightweight construction are used as a basis for deriving the technically relevant criteria for designs and material concepts. The work conducted in this field today centres around the synthesis of construction method and material development with the objective of devising a multi-material-design [1,2]. Modularisation is an economic approach aimed at shaping the diversification of the vehicle concepts and implementing this effectively [3]. As a result of hybrid and later fuel cell drives, the requirements on the vehicle concepts will continue to grow in future. Modularisation also sometimes opposes the striving for a high level of integration. The modular lightweight concept of the DLR aims at designing powertrain evolutions in a scalable and cost-efficient manner and in a way that retains the concept flexibility or, in some cases, even increases this. These approaches lead to the strategy known as "hybrid~3 . This strategy not only involves matching different materials and various construction methods with each other, but also taking account of the integration of functional effects. This entails, for example, optimising the design of thin-walled structural components in terms of their vibratory or acoustic properties with structure-integrated, active materials. Further examples of the approach with "hybrid " effects could be selectable surfaces or integrated energy conversion. The various development directions are depicted in the form of a roadmap and discussed on the basis of forward-looking examples from the field of vehicle construction. Designs and material concepts One way to achieve the objective of reducing CO_2 emissions is by decreasing the driving performance inhibiting factors. By means of a specific lightweight design, it is possible to reduce the masses and, as such, the driving performance inhibiting factors, such as acceleration, rolling and incline resistance. The body construction methods 'monocoque', 'stressed skin', 'space frame' and their hybrid forms consisting of stressed skin and space frame, exert a tremendous influence on the properties and design of a vehicle. By adapting the elements, the space frame construction method, for example, allows the body shape to be scaled.