Functionally graded zirconium oxide coatings produced on zirconium using induction heat treatment

摘要

Zirconium oxide coatings were produced by induction heat treatment (IHT) of E110 zirconium. The IHT was performed at temperatures within 600-1200 degrees C for 30-300 s. According to the results of scanning electron microscopy (SEM), energy dispersive analysis (EDX), X-ray diffraction (XRD), and nanoindentation, zirconium oxide coatings with high hardness of 44.56 +/- 7.40 GPa (at load of 10 mN), 25.76 +/- 2.78 GPa (at load of 200 mN), and elastic modulus of 387 +/- 55 GPa (at load of 10 mN), 372 +/- 20 GPa (at load of 200 mN) were formed on zirconium by IHT at 800-850 degrees C for 300 s. The functionally graded oxide coatings consisted of a mixture of alpha-ZrO2 (baddeleyite) and gamma-ZrO2 (cubic zirconia), the oxygen concentration on the surface reached a maximum of 69.52 +/- 3.16 at% and the thickness of the oxygen-rich layer was about 8-10 mu m.