High-Temperature Oxidation Behavior of Sputtered Ni20Cr Nanocrystalline Coating

A sputtered Ni20Cr nanocrystalline coating was prepared by means of magnetron sputtering. The isothermal oxidation and cyclic oxidation behaviors of the Ni20Cr nanocrystalline coating were investigated at 1000 ℃ in air. The results showed that a continuous oxide scale was formed on the surface of the nanocrystalline coating at 1000 ℃, and the scale consisted mainly of Cr2O3 with a little NiCr2O4. No obvious cracks were observed on the nanocrystalline coating, and a fine-grain structured and compact scale was formed on the nanocrystalline coating after 100 cycles of oxidation at 1000 ℃, indicating that the cyclic oxidation resistance of the sputtered nanocrystalline coating is better than that of Ni20Cr alloy.