MECHANICAL-PROPERTIES AND STRAIN EFFECTS IN BI2SR2CACU2OX AGMG COMPOSITE CONDUCTORS/

The development of powder-in-tube Bi2Sr2CaCu2Ox technology has progres sed such that high critical current density (J(c)) conductors are prod uced by many researchers. Prototype systems are being tested to demons trate engineering feasibility. An important issue that remains, howeve r, is the effect of mechanical strain, While it is evident that large strains induce irreversible damage, applications may be limited by fat igue at low strain values due to crack propagation. Here we report on the development of two devices designed specifically to study strain e ffects in high temperature superconducting tapes. Preliminary results of the effects of cyclic fatigue on J(c) of AgMg-clad Bi2Sr2CaCu2Ox as measured by electrical transport is shown. Measurements of the consti tuent and composite mechanical properties are also reported.