Lightweight linear cellular composite materials on basis of austenite stainless TRIP-(TRansformation Induced Plasticity-) steel as matrix with reinforcements of MgO partially stabilized zirconia (Mg-PSZ) are described. Two-dimensional cellular materials for structural applications are conventionally produced by sheet expansion or corrugation processes. The presented composites are fabricated by a modified ceramic extrusion powder technology. Characterization of the microstructure in as-received and deformed conditions was carried out by optical and scanning electron microscopy. Magnetic balance measurements and electron backscatter diffraction (EBSD) were used to identify the deformation-induced martensite evolution in the cell wall material. The honeycomb composite samples exhibit an increased strain hardening up to a certain engineering compressive strain and an extraordinary high specific energy absorption per unit mass and unit volume, respectively. Based on improved property-to-weight ratio such linear cellular structures will be of interest as crash absorbers or stiffened core materials for aerospace, railway, or automotive applications.

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The employment of ferritic nodular cast iron for components subjected to high stress requires a detailed fracture mechanics evaluation of crack growth under static and cyclic loading. During operation, for instance, in wind power plants, such component parts are subjected to loading of variable amplitude, which influences their lifetime considerably. For the evaluation of crack propagation and the remaining service life in this case, the calculation methods currently well-established in practice cannot be employed for cast iron with nodular graphite, since overloads lead to microstructure-related and material-specific load history effects in terms of crack growth acceleration. In this work, investigations of crack growth under constant and variable amplitude loading as well as static fracture toughness investigations and strain-controlled cyclic deformation experiments are presented.

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