Distinguishing Features of Phase Transformation in the Surface Layer of Hardened Steel with (α+γ)-Two-Phase Structure during Plasto-Elastic Loading at Different Rates

An effect of loading during uniaxial tension at different rates ranging from 10 -4 to 10 -2 s -1 on the phase transformation "austenite-martensite" in the surface layer of hardened 0.36%C-14%Νi steel type with an unbalanced (α + γ)-structure has been determined by an X-ray structure analysis.The mechanisms of (γ-s)-transformation through the depth of steel surface layer and character of this transformation propagation along the specimen length depending on external stress value and tension rate have been defined.