Sensitivity of Nb3Sn Rutherford-type cables to transverse pressure

Fermilab is developing high field superconducting magnets for future accelerators based on Nb3Sn strands. Testing the critical current of superconducting cables under compression is a means to appraise the performance of the produced magnet. However, these cable tests are expensive and labor-intensive. A fixture to assess the superconducting performance of a Nb3Sn strand within a reacted and impregnated cable under pressure was designed and built at Fermilab. Several Rutherford-type cables were fabricated at Fermilab and at LBNL using multifilamentary Nb3Sn strands. The sensitivity of Nb3Sn to transverse pressure was measured for a number of Nb3Sn technologies (Modified Jelly Roll, Powder-in-Tube, Internal Tin, and Restack Rod Process). Results on the effect of a stainless steel core in the cable are also shown.