Transition in deformation behavior of martensitic steel during large deformation under uniaxial tensile loading

More than 50% elongation of as-quenched martensite was achieved under uniaxial tensile loading using a multilayered structure combining martensitic and austenitic steel, and the deformation behavior of as-quenched martensite was observed in situ. It was demonstrated that work-hardening of as-quenched martensite is enhanced as applied strain exceeds a certain level, 15–20%, and that the transition from poor work-hardening to improved hardening is associated with a shift in the deformation mode of martensite.