On the mechanical properties of the advanced martensitic steel EUROFER 97

In an effort to better understand the plasticity of tempered martensitic steels, uniaxial tension and compression tests were carried out. The temperature dependence of both the yield stress and the post-yield stress behavior were compared, and it was shown that a good correspondence exists between tensile and compressive behavior. The strain-hardening of EUROFER 97 steel was examined in terms of dislocation mechanics. A simple strain-hardening law was established within the framework of a model accounting for dislocation storage and annihilation. Moreover, an analytical constitutive equation was derived which describes the overall post-yield curve. While the equation predicts the flow stress should reach a saturation stress with strain, this could not be verified by the mechanical tests due to deformation instabilities such as necking in tension or side-slip buckling in compression. Additional tests will have to be devised and applied to investigate these predictions.