YBa_2Cu_3O_x体材料在液氮温区的临界电流密度J_c  

Critical Current Density of Bulk YBa_2Cu_3O_x Sample J_c at Liquid Nitrogen Temperature

作　　者：王魁汉[1] 樊占国[1] 冀春霖 曾桂仪[1] 刘素兰[1] 王士兰[1] 赵忠贤[2] 郑东宁[2] 

机构地区：[1]东北工学院 [2]中国科学院物理研究所

出　　处：《东北工学院学报》1989年第4期394-398,共5页

摘　　要：以定向反应合成的 YBa_2Cu_3O_x 为原料,用加大成型压力——高温熔化——三段热处理工艺,可将 YBa_2Cu_3O_x 体材料的 J_c 提高到 713 A/cm^2(78 K);讨论了晶粒间界的空隙,微区化学组成不均匀性,高温熔化及凝固过程对 J_c的影响。结果表明,采用较大压力成型,高温熔化工艺,提高碳酸盐分解率,有助于提高临界电流密度J_c。Superconducting YBa_2Cu_3O_x synthesized through directional reaction were usedas test samples. The critical current density of bulk YBa_2Cu_3O_x supercon-ductor, J_c,was found up to 713 A/cm^2(78K) after increasing pellet--formingpressure, high-temperature melting and, finally, a 3-step heat treatment. Theinfluences of the micro--porosity between grain boundaries, the inhomogeneityof chemical composition,high -temperature melting and solidification processon J. are discussed briefly. The results show that higher pelletforming press-ure,high--temperature melting and raised dissociation rate of barium carbonateare he1pful to enhancing J_c.

关 键 词：超导材料 液氮温区 临界电流密度 

分 类 号：TM26[一般工业技术—材料科学与工程]