Irradiation Effects Of Low-energy Ions On A Zirconium Alloy

In this study，irradiation simulation tests of120keV argon ion and nitrogen ion on azirconium alloy were carried out by using a positive ion irradiation facility. In order toinvestigate the low energy ion irradiation effect on this zirconium alloy, the influence ofargon ion and nitrogen ion irradiation on surface chemical composition and phaseconstitution, surface nano-hardness, tensile property, deformation and tribologicalbehaviors as well electrochemical characteristics have been evaluated by XRD, XPS,SEM, TEM, AFM, Nano-Indenter, wear, tensile test and electrochemical techniques.The results show that the argon ion irradiation has no remarkable effect on surfacechemical composition and phase constitution of the zirconium alloy. The trace ofamorphous formation in the argon ion irradiated specimen was detected by TEM. Afterargon ion irradiation, reduction in surface roughness ion irradiation was also observedby AFM, and no evident difference in tensile strength and fracture strain was found, butthe surface nano-hardness and scarification resistance of zirconium was seen to increase.The argon ion irradiation might harden surface, however did not affect surface crackpropagation. With the increase in fluence of argon ion irradiation, the averagecoefficient of friction of the alloy firstly increased and then decreased, and the crispabrasive were difficult to stick together. The corrosion resistance of the zirconium alloybecomes worse after argon ion irradiation, perhaps due to argon ion denudation effecton the thin zirconia layer.After the zirconium alloy irradiated by120keV nitrogen ions, formation of a smallamount of nitrogen compounds was detected by XPS, and amorphous phase wasobserved by TEM, as well as increase in surface roughness was found by AFM. Noremarkable difference in tensile strength and fracture strain was detected before andafter nitrogen ion irradiation, but the surface nano-hardness and scarification resistanceof the irradiated zirconium alloy was found to increase. The nitrogen ion irradiationcould harden surface, but also did not affect surface crack propagation. With theincrease in fluence of nitrogen ion irradiation, the average coefficient of friction of thealloy firstly increased and then decreased, and the crisp abrasive was seen to easily tostick together. The corrosion resistance of the zirconium alloy becomes better after nitrogen ion irradiation, owing to the amorphous and nitrogen compounds produced onthe surface.