BaCuO_(2-δ)含量对GdBaCuO超导块材结构和磁浮力性能的影响

Effects of BaCuO_(2-δ) Addition on Microstructure and Levitation Force for Gd-Ba-Cu-O Single-domain Superconductors

采用Nd-Ba-Cu-Mg-O冷籽晶和熔融织构生长工艺,在空气气氛下制备出GdBaCuO单畴块材,并通过流通氧气气氛退火处理获得超导样品。研究了前驱粉末中不同BaCuO2-δ含量对GdBaCuO前驱粉末熔化温度、块材生长及超导磁浮力性能的影响。结果表明,GdBaCuO前驱粉末的熔点随着BaCuO2-δ添加量的增加而降低。前驱粉末中BaCuO2-δ的添加量为0～0.5mol时,GdBaCuO块材均能生长成表面没有宏观裂纹、尺寸为Ф17mm的单畴,而BaCuO2-δ添加量为0.2mol时,样品的磁浮力性能最高,最大磁浮力密度达到12N/cm2(77K)。

Single-grain bulks of GdBaCuO were successfully prepared under the ambient atmosphere via cold seeds of Nd-Ba-Cu-Mg-O crystal and MTG. The superconducting samples were obtained at about 400 by flowing oxgyen atmosphere. The influence of BaCuO2-δ addtion on the melting temperature of GdBaCuO precursor powders, the growth of samples and the supercongducting levitation force properties were investigated. Results show that BaCuO2-δ powder doped in GdBaCuO can significantly decrease the melting temperature of GdBaCuO precursor powder. From 0 to 0. 5tool of BaCuO2-δ content in substrate, the single domain bulks with no macrocracks on the surface are prepared. The appropriate amount of BaCuO2-δ addtion（x=0. 2） can effectively improve the superconducting properties, the maximum levitation force density is about 12N/cm^2（77K）.