The effect of aging on the superconducting transition temperature and resistivity of Y-Ba-Cu-O ceramics after high temperature treatment

International Conference on Functional Materials and Nanotechnologies 2013

材料科学;物理学

Nikoghosyan, S.K.^1,2 ; Harutyunyan, V.V.^2 ; Baghdasaryan, V.S.^2 ; Mughnetsyan, E.A.^1 ; Zargaryan, E.G.^1 ; Sarkisyan, A.G.^1

International Scientific-Educational Center, NAS RA, Armenia^1

A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute) Foundation, Armenia^2

关键词: After high temperature;    Aging process;    Environmental conditions;    Fast process;    High temperature treatments;    Intergranular;    Storage time;    Structural phasis;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/49/1/012042/pdf
DOI  :  10.1088/1757-899X/49/1/012042

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Some changes in superconducting transition temperature Tcand normal resistivity r of YBa2Cu30xceramics are investigated as a result of the aging stimulated by high temperature treatment and slow cooling to room temperature followed by the storage under environmental conditions during 255 hours. It is shown that the changes of these parameters fall on three specific intervals of storage time ta. In addition, different types of aging processes: fast and slow ones are observed for the heat-treated samples. It is found that the fast processes are accompanied by a slight increase of r and Tcwithin the first interval of storage time ta(ta≤ 162 hrs.), while the slow processes correlate with a sharp decrease of Tcand simultaneous increase of r within the second aging interval (162 hrs. ≤ ta≤ 206 hrs.). It is revealed that the fast and slow aging processes result from the redistribution of atoms in intergranular weak and strong links, correspondingly. The probable reason of the observed results is the formation and coexistence of various structural phases including the semiconducing one.