空气中各组份对YBa_2Cu_3O_(7-δ)稳定性的影响

INFLUENCE OF AIR COMPONENTS ON THE STABILITY OF YBa_2Cu_3O(7-δ).

通过观察YBa_2Cu_3O_(7-δ)超导样品在空气的几种主要组份(氧气、氮气、二氧化碳、水蒸汽等)中磁化率和重量的变化,发现YBa_2Cu_3O_(7-δ)在空气中性能退化主要是由于“碳化”作用所致。尽管热力学分析表明这种“碳化”作用是可以自发进行的,但在干燥状态下YBa_2Cu_3O_(7-δ)实际上并不与Co_2发生反应。因此,水蒸汽的存在是导致YBa_2Cu_3O_(7-δ)在空气中不稳定的根本原因。

Variation of susceptibility and weight of YBa_2Cu_3O_(7-(?)) superconducting ceramics stored in oxygen, nitrogen, carbon dioxide and vapour were studied. The results show that the degeneration of YBa_2Cu_3O_(7-(?)) stored in air is resulted from carbonation, Although carbonation can occur automatically from thermodynamic analysis, in fact YBa_2Cu_2O_(7-(?)) does not react with CO_2 in dry condition. It is concluded that the presence of vapour is the basic reason for unstability of YBa_2Cu_3O_(7-(?)) stored in air,