Study on microstructural changes in thermally-aged stainless steel weld-overlay cladding of nuclear reactor pressure vessels by atom probe tomography

► Microstructural changes in stainless steel electroslag weld-overlay cladding. ► Thermal aging caused progress of spinodal decomposition and precipitation of G phases in the δ-ferrite phase. ► The degree of the spinodal decomposition had a linear relationship to the hardness.