摘要
采用 PHI-650 型扫描俄歇电子能谱(SAM)研究金属铀在超高真空原位断裂后断面在不同氧气暴露量和温度下的氧化规律和杂质元素在表面的扩散行为。实验中采用在主真空室内的装置在超高真空中打断铀样品,然后在 1×10-5 Pa的压力下充入暴露量为 5 L、20 L、70 L、170 L 和 270 L 的高纯氧气进行氧化实验并获取 U,O,S 和 C 的俄歇电子谱。实验结果表明:在 5 L 和 20 L 的氧气暴露量下表面形成 UO2 和金属 U 的混合物,在大于 70 L 情况下只形成 UO2。 在1×10-7 Pa 的真空中将 UO2 加热到 100℃,150℃,200℃和 300℃并进行 SAM 分析,结果显示:随温度的升高,尤其是在 300℃时元素 S 向表面扩散,形成明显的富集,且表面氧和铀的原子浓度比明显下降。
PHI-650 scanning Auger multi-probe (SAM) was used to study the surface oxidation and impurity element diffusion of the in situ fractured uranium surfaces at various oxygen exposure and temperatures in ultra high vacuum. The sample was fractured by the instrument of main vacuum chamber in ultra high vacuum. After fracture, the sample was exposed under 5 L, 20 L, 70 L, 170 L and 270 L oxygen and the Auger electron spectra of U, 0, S and C elements were recorded. The experimental results indicated that: Mixture Of UO2 and U was formed at 5 L and 20 L oxygen exposure, while at quantity of oxygen exposure more than 70 L unique UO2 was observed. Heating the oxidized fractured surfaces to 100degreesC, 150degreesC, 200degreesC and 300degreesC showed that: at high temperature, especially at 300degreesC, element S diffused to the surface and enrichment of S at surface was observed, at the same time, ratio of atomic concentration of oxygen to uranium decreased obviously.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2004年第11期1182-1185,共4页
Rare Metal Materials and Engineering
关键词
铀
原位
断裂表面
SAM
初期氧化
uranium
in situ
fracture surface
SAM
initial oxidation
