( 中国工程物理研究院， 绵阳 621900)
摘 要: 研究了铀表面磁控溅射离子镀Ti/Al复合镀层在200~500℃温度范围， 分别在0.05 MPa的O2、 H2O和HCl气体中的腐蚀失效形式。 采用俄歇电子能谱（AES）分析了腐蚀后腐蚀介质元素在复合镀层中的深度分布，并采用有限元分析方法计算了在腐蚀加热和冷却过程中复合镀层的应力变化。 结果表明： O2、 H2O、 HCl引起铀表面Ti/Al复合镀层的反应腐蚀温度依次降低，界面分离是Ti/Al复合镀层抗气体加热腐蚀的主要失效形式， Al/U和Ti/Al界面分别成为Ti/Al复合镀层在含O气氛和HCl气体中加热腐蚀的薄弱环节； 镀层从界面剥离主要是腐蚀气体从镀层缺陷渗透到界面，降低界面的结合力， 从而产生应力引起的。
关键字: Ti/Al复合镀层；铀； 腐蚀； 界面； 应力
（ Chinese Academy of Engineering Physics,
Mianyang 621900, China）
Abstract: The corrosive behavior of Ti/Al dual coating on uranium prepared by magnet-sputtering ion plating technique was investigated under the condition of 0.05MPa O2， H2O or HCl atmosphere at 200-500℃. The depth profile of corrosive elements in Ti coating was analyzed by Auger Electron Spectroscopy(AES). The stress distribution in the dual coatings was evaluated by the finite element method during rising and cooling processes. The reaction temperature of the Ti/Al dual coating with O2, H2O and HCl gases was found to be decreased. The Ti/Al dual coating on uranium was spalled at Al/U interface after hot corrosion in O2 and H2O atmosphere, and Ti coating was separated from Ti/Al interface in HCl atmosphere. Both Al/U and Ti/Al interfaces of the Ti/Al dual coating on uranium are the worst anti-corrosion region against O2, H2O and HCl gases. The stress leads to failure of the dual coating at the interface after O or Cl element diffuses into the interface and reacts with the metal.
Key words: Ti/Al dual coating; uranium; corrosion; interface; stress
