Abstract
The increasingly demanding requirements for vehicles concerning safety, emissions and user comfort are a main driver for knowledge acquisition on structural reinforcement technologies that enhance the overall vehicle performance. Besides, the evaluation of mechanical and physical benefits, an estimation of the consequential cost of these technologies as well as the environmental impact that is associated with it need to be known as they provide the industry with a complete cost-benefit analysis of available technologies.
Based on an extensive literature study, a high-level cost-benefit analysis is made, including over 20 technologies. Apart from mechanical and physical properties, other key issues such as recyclability, modularity and functional integration are considered as well and rated from a qualitative point of view. Next, the most interesting technologies are quantified in more detail with respect to their properties and environmental impact. Simultaneously, a cost estimation is drawn up as well, resulting in a complete and detailed cost-benefit comparison of reinforcement technologies. In a later stage, this information will be used to select the most promising technology for the industrial applications provided by industrial partners1.
In a first series of tests, two preformed foam types (XPS and PMI) and one injected 2C-PUR foam have been evaluated on their reinforcing effect in metal profiles based on bending and impact tests. Surprisingly, the PMI foam showed significantly higher energy absorption-to-weight ratios for the low-density variant compared to the high-density variant. Due to the rather low density of the XPS foam, this material had no effect on the mechanical properties of the metal profiles. Furthermore, the filling degree of the injected foam appeared to have a significant positive effect on energy absorption during impact.
KEYWORDS – hollow structures; polymer foams; energy absorption; stiffness