Nondestructive assessing of the aging effects in 2205 duplex stainless steel using thermoelectric power

The microstructural transformation of ferrite into secondary austenite and sigma phase during long term exposure to high-temperatures (650–900 °C) in a 2205 duplex stainless steel has been investigated using the thermoelectric power (TEP) technique, scanning electron microscopy (SEM), Charpy-impact test (CIT), equivalent ferrite and sigma phases content measurements. The possibility of using the TEP coefficient as a nondestructive assessment technique to characterize the aging kinetics of 2205 duplex stainless steel is discussed. Experimental results indicate that TEP coefficient is sensitive to the gradual microstructural transformation of ferrite phase experienced by the 2205 duplex stainless steel during the aging treatments.