Project Leader: Otmar Kolednik

Steels with the transformation-induced plasticity (TRIP) effect exhibit phase transformations of austenite into martensite triggered by plastic deformation. This transformation enhances strain hardening, which leads to a combination of excellent strength and ductility. In spite of the fine microstructure of the material investigated, the deformation induced phase transformation of single austenitic grains can be studied using high-resolution scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The accompanying transformation strains in the surrounding matrix can be quantified by local deformation measurements.

Local deformation measurements are based on a system for digital image analysis which finds identical points on SEM-micrographs captured at different deformation stages. The method provides, with high accuracy and resolution, the local in-plane strains that occur in the loading step considered. A similar digital image analysis system has been applied for quantitative fracture surface analysis.

Deformation- and fracture behavior of advanced materials

Important publications on similar topics

J. Stampfl, S. Scherer, M. Berchthaler, M. Gruber, O. Kolednik, Determination of the fracture toughness by automatic image processingInternational Journal of Fracture 78(1996) 35-44.

C.O.A. Semprimoschnig, J. Stampfl, R. Pippan, O. Kolednik, A new powerful tool for surveying cleavage fracture surfacesFatigue & Fracture of Engineering Materials and Structures 20 (1997) 1541-1550.

A. Tatschl, O. Kolednik, A new tool for the experimental characterization of micro-plasticityMaterials Science and Engineering A339 (2003) 265-280.

A. Tatschl, O. Kolednik, On the experimental characterization of crystal plasticity in polycrystals". Materials Science and Engineering A364 (2004) 384-399.

O. KolednikThe characterization of local deformation and fracture properties – a tool for advanced materials designAdvanced Engineering Materials 8 (2006) 1079-1083.

A. Musienko, A. Tatschl, K. Schmidegg, O. Kolednik, R. Pippan, G. Cailletaud, 3D Finite Element simulation of a copper polycrystalline specimenActa Materialia 55 (2007) 4121-4136.

M. Kapp, T. Hebesberger, O. Kolednik, A micro-level strain analysis of a high-strength dual-phase steelInternational Journal of Materials Research 102 (2011) 687-691.

Zechner, M. Janko, O. Kolednik, Determining the fracture resistance of thin sheet fiber composites – Paper as a model materialComposites Science and Technology 74 (2013) 43-51.