辉光等离子体氮化铀表面的氢腐蚀

采用辉光等离子体氮化方法制备铀表面氮化样品。俄歇电子能谱和X射线衍射对样品的分析表明，铀表面形成了厚约250 nm、主要成分为α-U₂N_3+x的氮化层，氮化层与基体之间具有平缓的过渡层，且氮在金属铀的基体内有一定扩散。与轻微氧化样品氢腐蚀的对比实验表明，氮化处理使样品表面缺陷密度减少，改性层对氢吸附、扩散有阻挡作用，氢蚀形核较慢且其生长明显受到改性层的抑制，这表明铀表面辉光等离子体氮化可作为延缓氢腐蚀的有效手段。

Hydriding Behavior of Glow-Discharge Plasma Nitrided Uranium Surface

Surface nitrided uranium was prepared using glow-discharge plasma nitriding method.The surface layer was examined and a comparison between surface nitrided and oxidized against hydrogen corrosion was monitored with a digital microscope.AES depth profile and XRD spectrum show that the surface-nitrided layer is about 250 nm in sputtering depth and mainly consists of α-U₂N₃+x,with a mild nitride-substrate interface and nitrogen diffuses into the metal bulk.SEM micrographs show that pulsed glow-discharge plasma nitriding can reduce the number of polishing scratches and other defects.Surface nitride layer retards hydrogen diffusion into bulk,delays the nucleation and restrains hydride growth.Glow-discharge plasma nitriding can passivate uranium surface against hydrogen corrosion effectively.