Experimental investigation of hybrid material systems consisting of advanced composites and sheet metal

Previous studies have identified composite-metal hybrid material systems in automotive crash structural applications as a possible solution to meet the demands of both ambitious efficiency goals and increasingly strict vehicle safety requirements. The purpose of this study is to experimentally identify basic principles, which define the material systems' properties such as the stiffness and strength as well as major parameter effects on a coupon scale. A further aim is to compare these findings to common approaches such as the rule-of-mixture theory and define analytical models able to predict these properties based on a set of parameter values. While there is a strong dominance of the steel phase, the experiments generally confirm the rule-of-mixture theory. Some effects might have to be considered when designing hybrid material systems for technical applications, such as the shift of the special neutral plane in asymmetric layups or a changed failure mode for different loading directions. The analytical models presented do match the experimental results, although the complex interaction between the material phases is not fully analyzed.