MEASURE OF THE MAGNITUDE OF YOUNG MODULUS IN WHISKER-LIKE SAMPLES OF THE BI-BASED HIGH-TC MATERIALS BI2SR2CACU2OX AND BI2SR2CA2CU3OX

We have measured Young's modulus in ribbon-like whisker samples of the high-T(c) materials: Bi2Sr2CaCu2Ox and Bi2Sr2Ca2Cu3Ox. This is the first direct measurement of Young's modulus for whiskers of any of the high T(c) materials. We used a stress-strain probe that applies an axial force (uniaxial stress) to the whisker-like sample and simultaneously measures the corresponding sample elongation. The slope of the resulting stress-strain curve yields the magnitude of Young's modulus (Y). We found these Bi based high-T(c) materials to be soft with Y almost-equal-to 20 GPa for Bi2Sr2CaCu2Ox and Y almost-equal-to 25 GPa for Bi2Sr2Ca2Cu3Ox.