Study On The Uranium Modified Surface Layer Obtained By Ion Implanted With Niobium At High Temperature

By the technology of ion implantation at high temperature, the modified surface layer by ion implanted with niobium at high temperature on the uranium has been studied in this paper. The distribution and the constitution of elements on the uranium modified surface layer obtained by ion implanted with niobium at high temperature were analyzed by Auger Electron Spectroscopy (AES) and X-ray Diffraction (XRD). Based on the results of the test on the modified surface layer's corrosion resistance abilities, the contrast between the corrosion resistance abilities of the uranium modified surface layer obtained by ion implantation with niobium at high temperature and that obtained by ion beam assisted deposition(IBAD) with niobium was showed in the paper. And the difference of corrosion resistance abilities between uranium modified surface layer and the uranium-niobium alloy has also been discussed.The results of the experiment indicate that contrast with the uranium modified surface layer obtained by normal ion implantation, that obtained by ion implantation with niobium at high temperature is thicker and has more persistent dose. With the growing temperature, the construction of the uranium modified surface layer changes. The changes include the creation of the unbalanced phase and the creation of NbO and NbO₂ on the layer's surface at high temperature.The uranium modified surface layer obtained at high temperature has more advantages of corrosion resistance than that obtained by normal. With the growing of the temperature, the self-corrosion resistance voltage of the uranium modified surface layer becomes higher and the corrosion resistance abilities improve, too. The anodization changes of the niobium ion sample implanted to the uranium surface at different temperatures have a same tendency.In contrast to the uranium modified surface layer obtained by ion implantation with niobium at high temperature, that obtained by IBAD is obviously thicker and has a better construction. However, the uranium -niobium alloy has a higher self-corrosion resistance voltage and stronger corrosion resistance than modified surface layer.Due to the ion implantation temperature which is about 300℃, the modified surface layer is too thin to protect uranium surface for a long time. To improve the corrosion resistance ability of the modified surface layer, more advanced instruments by which the layer's thickness can get an improvement should be taken account of. By the work in this paper, wecan come to the conclusion that ion implantation is an effective technology to improve the uranium surface.