The Effect Of Thermal Cycling On Steam Oxidation Behaviour Of Tp347h Fg At 650 Degrees C

The cyclic oxidation behaviour of fine-grained Type 347 stainless steel (TP347H FG) at 650 degrees C in air saturated steam and deoxygenated steam environments for 100-1000 h has been investigated. Electron microscopy, Energy Dispersive and Wavelength Dispersive X-ray Spectroscopy (EDS and WDS, respectively) have been used to characterise the samples. Short term oxidation tests have shown only haematite spallation occurs whereas longer term tests have shown magnetite also spalls on cooling to room temperature. In all cases cyclic oxidation showed spallation does not occur after long term tests and is only visible in small amounts after short term tests subsequent to the initial spallation event.