Influence of Bimetal Structure and Phase Composition on Localized Plastic Strain

The paper investigates the macrolocalization of plastic strain due to uniaxial loading of low carbon/austenitic stainless steel produced by electron-beam additive manufacturing followed by annealing at different temperatures. The stress-strain curve of the bimetallic composite is described by the parabolic law. Due to annealing in the range of 350 to 650°C, the yield strength reduces, while strain-to-failure grows as compared to the as-built composite. Localized plastic strain follows the stress-strain curve in all composite states and layers. At the parabolic hardening stage, the formation of a stationary dissipative system of localized plasticity occurs at strain hardening of 0.5. When strain hardening is ≤0.5, a high-amplitude deformation zone appears in the transition layer, which coincides with the site of eventual fracture.