Corrosion Behavior of Pre-oxidized GH4169 Alloy with Solid NaCI Deposited in a Wet Oxygen Flow at 600 ℃

The corrosion behavior of the pre-oxidized GH4169 alloy was studied after 20 h of exposure under a solid NaCl deposit film in a wet O_(2) environment at 600℃ by mass-gain measurements,X-ray diffraction,scanning electron microscopy,transmission electron microscopy methods.The results indicate that the pre-oxidized GH4169 alloy undergoes serious corrosion in the corrosive condition.The preformed Cr_(2)O_(3) layer is gradually destroyed by deposit NaCl,and the inner Nb2O5 layer beneath the complete outer Cr_(2)O_(3) layer also reacts with NaCl to form NaNbO_(3).The electrochemical test results testified the existence of electrochemical reactions during this corrosion process.The corrosion behavior of pre-oxidized GH4169 under a solid NaCl deposit film in a wet O_(2) environment at 600℃has been discussed in detail.