FAST TABLE TOP NIOBIUM HYDRIDE INVESTIGATIONS USING DIRECT IMAGING IN A CRYO-STAGE.
FAST TABLE TOP NIOBIUM HYDRIDE INVESTIGATIONS USING DIRECT IMAGING IN A CRYO-STAGE.
复制标题
在低温阶段使用直接成像进行快速台式氢化铌研究。
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
A. Grassellino
中科院分区：
文献类型：
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作者：
F. Barkov;A. Romanenko;A. Grassellino
有损的非超导Nb氢化物的沉淀是高纯Nb在超导应用中的一个已知问题。利用低温光学显微镜和激光共聚焦扫描显微镜，我们直接观察到了超导射频腔不同处理后样品中Nb氢化物的表面析出和演化。氢化物的生长过程可用快速扩散控制过程很好地描述，在T=140K，∼30min内几乎全部析出氢气。120◦C烘烤和机械变形对氢化物析出的影响是通过影响形核和俘获中心的数目来实现的。
Precipitation of lossy non-superconducting niobium hydrides represents a known problem for high purity niobium in superconducting applications. Using cryogenic optical and laser confocal scanning microscopy we have directly observed surface precipitation and evolution of niobium hydrides in samples after different treatments used for superconducting RF cavities. The growth of hydrides is well described by the fast diffusion-controlled process with almost all hydrogen precipitated at T = 140 K within ∼ 30 min. 120 ◦ C baking and mechanical deformation are found to affect hydride precipitation through their influence on the number of nucleation and trapping centers.