贫铀表面激光氮化层的结构和氧化动力学研究  

Structure and Oxidation Kinetics of Nitride Layer on Uranium by Pulsed Laser

作　　者：张延志[1,2] 张永彬[1] 管卫军[2] 陈志磊[1] 胡殷[1] 刘柯钊[1,2] 汪小琳[2] Zhang Yanzhi;Zhang Yongbin;Guan Weijun;Chen Zhilei;Hu Yinl;Liu Kezhao;Wang Xiaolin(Science and Technology on Surface Physics and Chemistry Laboratory,Mianyang 621907,China;China Academy of Engineering Physics,Mianyang 621900,China)

机构地区：[1]表面物理与化学重点实验室,四川绵阳621907 [2]中国工程物理研究院,四川绵阳621900

出　　处：《稀有金属材料与工程》2018年第8期2506-2510,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(U1630250)

摘　　要：为了研究激光氮化对金属铀表面结构和性质的影响,利用X射线衍射结合原位高温反应器,研究了不同激光氮化工艺后的贫铀表面结构,并对不同温度下UN的氧化过程进行了原位XRD实验分析,获得了相应条件下的氧化动力学曲线。结果显示,激光扫描速率对贫铀表面氮化层的相结构有显著影响,较快的扫描速率能够获得单一的UN结构,较慢的扫描速率将获得UN和U_2N_3的双相混合层。氧化动力学实验表明,表面激光氮化制备的UN层对基材有很好的保护作用,能够显著降低金属铀的氧化腐蚀速率。较低的温度下UN层的氧化非常缓慢,温度升至180℃以上时氧化速率明显加快,其氧化动力学曲线与贫铀有明显差异,文中对此现象和氮化层的氧化机制进行了分析和讨论。In order to study the effect of pulsed laser nitriding on uranium, the crystal structure and oxidation kinetics of a nitride layer on depleted uranium surface were investigated using X-ray diffraction and in situ reactor chamber. The results indicate that the crystal structure of nitride is affected by the scanning speed of pulsed laser remarkably. The UN is the sole nitride at high scanning rate while the mixed structure of UN and U2N3 is achieved at slow scanning rate. The UN layer by pulsed laser nitriding can protect the substrate and decrease the oxidation corrosion rate of uranium. The oxidation kinetics of uranium is slow in the extreme when the surface is covered with a layer of UN. However, the oxidation becomes fast when the temperature increases to 180℃. The oxidation kinetics of UN is quite different from that of the depleted uranium. The oxidation kinetics and oxidation mechanism of the nitride layer were also discussed

关 键 词：氮化铀 结构 氧化动力学 激光氮化 

分 类 号：O614.62[理学—无机化学]