Influence of Morphology of Deformation Induced α´-Martensite on Stress-Strain Response in a Two Phase Austenitic-Martensitic-Steel

In this research work specimens of the metastable austenitic steels AISI 304 and AISI 347 with one phase (fully austenitic) and two phase (austenitic-α ́-martensitic) microstructure were monotonically loaded at ambient temperature. Using stress-strain and temperature measurements the deformation behavior was characterized in detail. To study the influence of morphology of deformation induced α ́-martensite on the stress-strain response a phase field model for α ́-martensite transformations was developed. With this approach it was possible to model the two phase austenite-α ́-martensite microstructure and investigate the deformation behavior on the micro level. With optical microscopy, magnetic and x-ray measurements the microstructure characterization of fully austenitic and austenitic-α ́-martensitic steels was realized