Cu Precipitation-Mediated Formation of Reverted Austenite During Ageing of a 15–5 PH Stainless Steel

A Cu precipitation-mediated austenitic transformation during ageing treatment of a 15-5 PH stainless steel is revealed through atom probe tomography, in situ synchrotron X-ray diffraction and computational thermodynamics and kinetics. The austenitic transformation is proposed to occur through the pathway: Cu precipitation at the martensite/retained austenite interfaces or at martensite lath boundaries -> partitioning of austenite stabilizing elements towards interfaces of the Cu precipitates -> reverted austenite formation. (c) 2021 The Author(s). Published by Elsevier Ltd on behalf of Acta Materialia Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )