EFFECT OF ADDITION OF A SMALL AMOUNT OF SILVER ON THE MICROSTRUCTURE AND MECHANICAL-PROPERTIES OF YBA2CU3O7-X

More than 10 vol.% silver inclusions is frequently added to YBa2Cu3O7- x (Y123) compound to improve its mechanical properties. In the present study, the effect of a small amount (less than 10 vol.%) of silver in clusions on the microstructure and the mechanical properties of Y123 i s investigated. The presence of silver inclusions induces a liquid pha se of Y123. The liquid phase is localized around the silver inclusions , and large pores and dense domains are therefore formed. The strength and toughness of the composites also decrease by 60 and 16%, respecti vely, as 2.5 vol.% silver is added. The present study indicates that m ore than 5 vol.% silver is needed in order to improve the mechanical p roperties of Y123.