Optimization of composition and structure of electrodeposited Ni-Cr composites for increasing the oxidation resistance

Electrodeposited Ni-Cr composites integrate Cr particles (mean size 14 mu m) with a Ni matrix. Oxidation at 900 degrees C shows that although the as-deposited composite Ni-34Cr (by wt.%) forms a NiO scale, increasing the Cr content to 47 or annealing pre-treatment in vacuum at 700 degrees C results in the formation of a Cr2O3 scale. The result also shows that adding CeO2 particles into the Ni-34Cr composite can lower the oxidation kinetics, no matter whether the composite grows NiO or Cr2O3 after annealing. The effects of the particle content increase, annealing treatment and CeO2 addition on oxidation of the composite are discussed. (C) 2012 Elsevier Ltd. All rights reserved.