Influence of nitrogen ion implantation on the aqueous corrosion behavior of zircaloy-4

In order to study the effects of nitrogen ion implantation on the corrosion behavior of zircaloy-4, specimens were implanted with nitrogen ions using an accelerator with a dose range from 4×1014 to 5×1016 ions/cm2 at about 40 °C. Three-sweep potentiodynamic polarization measurement was employed to evaluate the aqueous corrosion behavior of zircaloy-4 in a 0.5 M H2SO4 solution. Scanning electron microscopy (SEM) was used to observe the topographies of nitrogen-implanted zircaloy-4 before and after potentiodynamic polarization curve measurement (POL) measurement the surface graphic character and the change of microstructures were examined by transmission electron microscopy (TEM). It was found that a significant improvement was achieved in the corrosion resistance of zircaloy-4 compared with that of the as-received zircaloy-4. The mechanism of the corrosion behavior of nitrogen-implanted zircaloy-4 was discussed.