title: Influence of Twisting and Bending on theJcandn-value of Multifilamentary MgB2Strands.
abstract: The influences of strand twisting and bending (applied at room temperature) on the critical current densities,Jc, andn-values of MgB2multifilamentary strands were evaluated at 4.2 K as function of applied field strength,B. Three types of MgB2strand were evaluated: (i) advanced internal magnesium infiltration (AIMI)-processed strands with 18 filaments (AIMI-18), (ii) powder-in-tube (PIT) strands processed using a continuous tube forming and filling (CTFF) technique with 36 filaments (PIT-36) and (iii) CTFF processed PIT strands with 54 filaments (PIT-54). Transport measurements ofJc(B)andn-value at 4.2 K in fields of up to 10 T were made on: (i) PIT-54 after it was twisted (at room temperature) to twist pitch values,Lp, of 10-100 mm. Transport measurements ofJc(B)andn-value were performed at 4.2 K; (ii) PIT-36 and AIMI-18 after applying bending strains up to 0.6% at room temperature. PIT-54 twisted to pitches of 100 mm down to 10 mm exhibited no degradation inJc(B)and only small changes inn-value. Both theJc(B)andn-value of PIT-36 were seen to be tolerant to bending strain of up to 0.4%. On the other hand, AIMI-18 showed ±10% changes inJc(B)and significant scatter inn-value over the bending strain range of 0-0.6%.
authors.affiliation: Center for Superconducting and Magnetic Materials, Department of Materials Science and Engineering, the Ohio State University, Columbus, OH, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Center for Superconducting and Magnetic Materials, Department of Materials Science and Engineering, the Ohio State University, Columbus, OH, USA.
authors.forename: G
authors.initials: G
authors.lastname: Li
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
authors.forename: M
authors.initials: M
authors.lastname: Susner
authors.affiliation: Center for Superconducting and Magnetic Materials, Department of Materials Science and Engineering, the Ohio State University, Columbus, OH, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Sumption
authors.affiliation: Hypertech Research, Columbus OH, USA.
authors.forename: M
authors.initials: M
authors.lastname: Rindfleisch
authors.affiliation: Hypertech Research, Columbus OH, USA.
authors.forename: M
authors.initials: M
authors.lastname: Tomsic
authors.affiliation: Center for Superconducting and Magnetic Materials, Department of Materials Science and Engineering, the Ohio State University, Columbus, OH, USA.
authors.forename: E W
authors.initials: EW
authors.lastname: Collings