Corrosion behavior of yttrium and cerium-implanted zirconium

In order to study the influences of ion implantation on the aqueous corrosion behavior of zirconium, specimens were implanted by yttrium and cerium ions with a fluence range from 1x10(16) to 1x10(17) ions/cm(2) at about 150degreesC, using MEVVA source at an extracted voltage of 40 kV. The valence of the surface layer was analyzed by X-ray photoelectron spectroscopy (XPS), three-sweep potentiodynamic polarization measurement was used to investigate the aqueous corrosion resistance of zirconium in a 1 mol/L H2SO4 solution. It is found that a significant improvement can be achieved in the aqueous corrosion behavior of zirconium compared with that of the as-received zirconium, when implanted yttrium ions fluence is more than 5 X 10(16) ions/cm(2). Glancing angle X-ray diffraction (GAXRD) was used to examine the phase transformation due to the cerium ion implantation in the oxide films. It was found that a remarkable decline in the aqueous corrosion behavior of zirconium implanted with cerium ions compared with that of the as-received zirconium. Finally, the mechanisms of the corrosion resistance behavior of the yttrium and cerium implanted zirconium are discussed respectively.