Stress partitioning and deformation induced martensitic transformation for TRIP-DP steels studied by in situ neutron diffraction

Tensile behavior of two commercially available TRIP aided dual phase steels was studied by means of in situ time of flight neutron diffraction. The deformation was characterized by three stresses, P 1, P 2 and P3; plastic flow starts in the ferrite matrix at P 1 and the deformation induced martensitic transformation and the plastic deformation in austenite occur respectively at P 2 and P 3, which are determined from neutron diffraction results. Work-hardening and a tensile strength versus uniform elongation balance are controlled by adjusting these three stresses. (author)