In situ observation of growth process of single domain YBCO superconductors

In situ observation of isothermal growth process of single domain YBCO bulk superconductors under different supercooling by top-seeded infiltration growth technique has been carried out via high temperature video camera. The research and analysis of macrographs of YBCO bulks under different growth time and supercooling are reported. It is found that the initial epitaxial growth temperature is about 1008℃ and the growth temperature window is ranged from 988℃ to 1008℃.The average growth rate of YBCO bulk increases with increasing supercooling and decreases with growth time when supercooling temperature is fixed, which is well consistent with the formula R a = a (Δ T ) b ; In addition, It is also discovered that the instantaneous growth rate is a random scattering data with time ranging from 0.01-0.72 mm h -1 , but the mean value of instantaneous growth rate linear increase with supercooling. These results are of great significance for fabricating high quality YBCO bulk.