Michael Schober

Dr.-Ing. Michael Schober

Research Area Characterization - C1:MicroMechInterface

Characterization and Modeling of the Interface Properties of Fiber Reinforced Polymeric Materials
Advisors: Gumbsch (IAM-CMS), Hohe (IWM Freiburg), Kuboki (UWO)

The mechanical characteristics of fiber reinforced polymers are highly dependent on the interface properties between the constituents of the composite material. In order to provide a deeper understanding of the damage and failure mechanisms of such interfaces, combined experimental and numerical investigations will be carried out. The main focus is directed to the damage and failure of the fiber-matrix interfaces under static load. Therefore, experimental investigations concentrate on tensile loads on the interface within microscale test specimens, which only contain a small number of fibers. The damage and failure of these specimens will be investigated by post-mortem fractography, and also by in-situ observation by means of optical microscopy. With the aid of experimental data for shear loadings and in consideration of the fractographic observations, the interface strength and toughness will be identified numerically by a reverse simulation of the experiment. Based on the experimental-numerical investigations, an interface damage model will be formulated, covering all aspects of damage and failure such as material properties, fiber preparation, and the local stress state. The model will be implemented and validated against experimental results and will be further employed in micromechanical simulations.

Fig. 1:  Schematic Failure of Fiber-Matrix-Interfaces

Fig. 2:  Microscale Test Specimen (bottom) with Corresponding Numerical Simulation (top)