Experimental Quantification of Phase Transformation in Austenitic Stainless Steel

This conference paper briefly discusses different techniques for measuring the evolution of the martensite content in cold-rolled stainless steel 301LN sheets under mechanical loading. Three methods are employed to measure the martensite content: (1) micrography, (2) bulk magnetic induction, and (3) local magnetic permeability measurements. The first two methods require the extraction of samples from the specimen while the third method allows for the in-situ monitoring of the martensite content. The results show that micrography provides only a poor accuracy in quantifying the martensite content, while the two magnetic methods yield satisfactory results. A ferritescope is used to perform the in-situ magnetic permeability measurements. The results from magnetic induction measurements are used to establish a relationship between the ferritscope output signal and the martensite content. A series of uniaxial experiments is carried out to investigate the effect of initial texture on the martensitic transformation kinetics.