The production of large (RE)Ba–Cu–O single grains ((RE)BCO), where RE = Y, Gd or Sm, of complex geometries is presently limited by the intrinsic slowness of the grain growth process. Additionally, the shapes achievable using established melt processing are constrained by the small number of post-processing techniques available. These materials are brittle and hard, which makes machining a difficult task and largely eliminates the possibility of producing highly intricate shapes. An alternative to this slow and inflexible growth process would be to join many small single grains to form one large composite grain, connected by high-performance superconducting joints. A reliable joining technique would also overcome the need for the careful and time-consuming post-growth machining processes. In this work we report on the use of single grain YBCO–Ag as an interface medium to achieve superconducting joints between (RE)BCO bulks. This joining technique is relatively quick and does not require tight process parameter control as there is no need to re-grow the interface joining material. We report on six joints produced from samples cut and joined in a variety of orientations. In addition, a joint was produced using bulk YBCO from two independent single grains. The trapped field properties of the resulting joined sample were measured and the microstructure at the joint was examined. We show that this simple but effective joining technique makes it possible to produce multiple composite grains with comparable superconducting properties to those of a single grain of the same size.

复杂几何形状的大 (RE)Ba-Cu-O 单晶粒 ((RE)BCO) 的生产目前受到晶粒生长过程固有缓慢的限制。此外，使用已建立的熔体加工可实现的形状受到可用的少量后加工技术的限制。这些材料又脆又硬，这使得加工成为一项艰巨的任务，并在很大程度上消除了生产高度复杂形状的可能性。这种缓慢且不灵活的生长过程的替代方法是将许多小的单晶粒连接起来形成一个大的复合晶粒，并通过高性能超导接头连接。可靠的连接技术还可以克服对细心和耗时的生长后加工过程的需求。在这项工作中，我们报告了使用单晶粒 YBCO-Ag 作为界面介质来实现 (RE)BCO 块体之间的超导接头。这种接合技术相对较快并且不需要严格的工艺参数控制，因为不需要重新生长界面接合材料。我们报告了从以各种方向切割和连接的样品产生的六个接头。此外，使用来自两个独立单颗粒的散装 YBCO 生产接头。测量所得接合样品的俘获场特性并检查接合处的微观结构。我们表明，这种简单但有效的连接技术可以生产多个复合颗粒，其超导性能与相同尺寸的单个颗粒的超导性能相当。