The influence of thermally induced matrix stresses on the superconducting properties of Nb<inf>3</inf>Sn wire conductors

Abstract

The superconducting critical temperature, T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</inf> , critical current density, J <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</inf> , and upper critical field H <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c2</inf> have been measured on bronze-processed Nb <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> Sn monofilament conductors prior to and after etching away the bronze matrix. Each superconducting parameter showed significant changes when the bronze matrix was removed. It is shown that the source of these changes are stress induced by thermal contraction of the bronze matrix.