Fabrication of non-superconducting and superconducting joints of Ag/Bi-2223 tapes by diffusion bonding

Diffusion bonding of multifilamentary Ag/Bi-2223 （ Bi2 Sr2 Ca2 Cu3Ox ） superconducting tapes has been performed successfally. Three types of joints, namely, with sih,er interlayer （type Ⅰ）, bonded directly （type Ⅱ）, with Bi-2212 （BizSr2Ca1 Cu2Ox ） powder interlayer or with Bi-2223 powder interlayer （type Ⅲ） were researched, respectively. The critical currents（ Ic ） of these joints were measured ond microstructures of the joints were evaluated by scanning electron microscope （SEM）. The result shows that type Ⅰ is non-superconducting joint with very low resistance, and type Ⅱ joint and type Ⅲ （with Bi-2212 or Bi-2223 ） joints are both of superconducting property. By comparing, type Ⅱ joint possesses most exceUent superconductivity, type Ⅲ joint with Bi-2223 powder interlayer takes the second place, and type ,任家烈 joint with Bi-2212 powder interlayer is least.