Damage and failure mechanisms of hybrid carbon fiber and steel fiber reinforced polymer composites

Fiber-reinforced plastics (FRPs) are widely used due to their superior properties but often suffer from brittle failure and poor structural integrity under impact loads. Metal fiber hybrids (MFH) offer a solution, but understanding their structure–property relationships remains challenging. This research provides a comprehensive mechanical characterization of a stainless steel-carbon fiber hybrid (SCFRP) embedded in epoxy resin, with a particular focus on the failure mechanisms and their influences. Therefore, the mechanical properties of the material, as well as the propagation and damage of the fracture, are investigated. In addition, three main failure mechanisms are identified and analyzed. The failure mode of a SCFRP laminate can be influenced by its composition, architecture, and specimen size and result from a combination of the blast effect of the brittle failing carbon fibers, the magnitude of the associated damage, and the movement of the fracture gap formation initiated by the carbon fiber failure.