F. Gehrig

Technische Universität Hamburg | TUHH

Here we present an in situ scanning electron microscopy (SEM) investigation of the compressive failure of unidirectional (UD) carbon fibre reinforced polymer (CFRP) composites with varying pre-existing void content. The experiments were carried out within a dual beam microscope, which couples a SEM with a focused ion beam (FIB), allowing sub-surfac...

The degradation under single axial fatigue loading of non crimp fabric composites is influenced by manufacturing defects as voids, fibre misalignments and poor resin wetting. A fast model has been developed by Gagel et al. to predict the fatigue life in accordance with micro damage mechanisms [1]. Experimental investigations of NCF based fibre comp...

The fracture behavior of conducting cracks in PZT (PIC 151) was investigated under combined mechanical and electrical loads in four-point bending. Controlled crack growth in a single-edge V-notch beam (SEVNB) specimen was achieved in a very stiff displacement controlled device. During the experiments a constant electric field was applied. The mecha...

The total (linear) energy release rate for crack growth in PZT ceramics and metal/ceramics interfaces is experimentally determined using a special modulation technique. In order to achieve stable crack growth a very stiff testing machine has been developed.

To measure the compression strength of unidirectional Carbon Fibre Reinforced Plastics (CFRP) is difficult. Various compression tests show significant inhomogeneous stress states, leading to a multiple failure mode. In the new approach different lubricants between specimen and loading equipment were tested to reduce multiaxial stress state in the l...