High-temperature oxidation of an alumina-coated Ni-base alloy

摘要

Alumina coatings were applied to Ni-20Cr (wt%) using combustion chemical vapor deposition (combustion CVD). Combustion CVD is an open air deposition technique performed in a flame. The oxidation kinetics of coated and uncoated specimens were measured by isothermal oxidation tests carried out in pure flowing air at temperatures of 800, 900, 1,000 and 1,100 C. The alumina coatings reduced the oxidation kinetics at all temperatures. The morphologies and compositions of the alumina coatings were characterized by transmission and scanning electron microscopy, energy dispersive x-ray spectroscopy and x-ray photoelectron spectroscopy.