Adherence of Nickel Oxide on Nickel during High Temperature Oxidation

摘要

A combined experimental/analytical study is being conducted to investigate the fundamental nature of adherence of oxide scales formed on metals during high-temperature oxidation. Isothermal oxidation experiments were conducted on high-purity nickel (Ni 270) specimens in air at temperatures of up to 1200/degree/C. None of the experiments resulted in physical separation of nickel oxide scales from nickel substrate, even though substantial amounts of porosity were found in scales close to the scale/metal interfaces. The results of numerical and analytical calculations of stresses in the NiO/Ni system suggest that metal and oxide plasticities play a role in the experimental observations. 10 refs., 5 figs., 2 tabs. (ERA citation 13:037076)