Prediction of irradiation hardening in austenitic stainless steels: Analytical and crystal plasticity studies

The flow stress in irradiated Austenitic Stainless Steels (ASSs) is analyzed in terms of the microstructure features and the fundamental mechanisms of plastic deformation. A set of constitutive equations is proposed to assess the contributions of dislocation network, grain size effect, dislocation loops and solute clusters, accompanied with an appropriate superposition rule. Using simple equations for the evolution of densities of dislocations and radiation defects, it is possible to integrate numerically the tensile stress-strain curves over a wide range of irradiation doses. It is shown that irradiation hardening can be obtained analytically without adjustable parameters. Simulation results are challenged in comparison with experimental results and found in excellent agreement with all the reported experimental trends in ASSs irradiated at conditions close to those prevailing in pressurized water reactors. (C) 2019 Elsevier B.V. All rights reserved.