High Temperature Oxidation Behaviour of Nimonic - 115 Alloy in Presence of Sodium Salts at 850OC

Document Type : Research Article

Author

Department of Chemistry, Faculty of Science and Technology,University College of Science and Technology Malaysia (KUSTEM),Mengabang Telipot, 21030 Kuala Terengganu, Terengganu Darul Iman, MALAYSIA

Abstract

The high temperature oxidation behaviour of Nimonic-115 industrial alloy has been investigated in presence of  NaNO3, Na2CO3 and Na2O2 at 850oC in flowing air. The oxidation kinetics and effect of salt deposition for the period of 48 h were studied. The scale morphologies were determined on the basis of X-ray diffraction analysis and Scanning electron microscopic techniques. It has been shown that the alloy corrodes at different rate in presence of different sodium salts although each salt contains the same amount of sodium equivalent to Na2O.

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