Abstract
The growth mechanism of the chromia scale formed in oxygen at 1 atm in the temperature range 785–985°C on Nimonic 86 (24.7% Cr, 10.2% Mo, 0.019% Ce, 0.011% Mg, 0.051% C, bal. Ni) has been studied using oxygen-18 as a tracer. The oxidation times ranged from 184 to 291 min. The location of the oxygen-18 was determined by means of charged-particle nuclear techniques. The scale grew primarily by oxygen transport, though the occurrence of scale buckling indicates that there was some cation diffusion. The cerium content of the scale was much greater than that of the alloy; as there is an optimum cerium concentration for maximum scale adhesion it is suggested that the scale buckling will expose alloy which contains less than this optimum amount.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call