1. Angular dependent I c at very high field in YBCO coated conductors A.Xu, Y. Viouchkov, J. Jaroszynski, D. Larbalestier NHMFL Tallahassee Y. Chen, Y.Y. Xie, V. Selvamanickam Super Power Inc. Motivation: a)to characterize J c ( , B, T = 4.2 K) for HTS magnet design b) to understand pinning mechanisms c) to explore how engineering of YBCO CC could enhance Jc ( , B, T)

2. High current probe with rotator current leads: YBCO tape in Cu braid sample platform drive: fishing line (kevlar) currents up to 500 A in 4.2 K angle -10 to 120 deg diameter: 1.5 in

3. Samples: full 4 mm width or etched to approx. 1 mm width glued by GE varnish: degeneration, delamination soldered to Cu PC board no degeneration

4. Results: T = 77 K; B = 1T Pronounced maxima around B||c in BZO doped samples red: “standard”, no BZO, M-3-513-FS I c (77K, SF) =123 A, YBCO t=2.17  m black: BZO #1 M3-594-1 BS Ic(77K, SF) =87 A, YBCO t=1.5  m blue: double layer “turbo” M3-609-1 MS Ic(77K, SF) =159 A, YBCO t=2.16  m

5. Angular I c (  ) at LHe temperature Very high in plane I c However: very sharp Ic(  ) dependence No c-peak No qualitative differences between different samples/tapes

6. Quick tests for low T high B properties I c Field dependence for B||c

7. Critical current @ T=4.2, B=14 T, B||c vs. T=77 K, SF B  ab

8. BZO doping makes ab-peaks wider

9. I c ( A / 4 mmw i d t h ) B ( T ) B ( T ) B ( T ) B ( T ) 0 deg 60 70 80 85 90 0 deg 60 70 80 85 90 0 deg 60 70 80 85 90 0 deg 60 70 80 85 90 At 20 deg off plane: upto 200 A at 30 T BZO doped sample: the highest Ic at 5 deg off I c vs. field @ 0/60/70/80/85/90 deg: different tapes

10. SP02 vs temperature

11. Standart B (SP02) vs temperature

12. Critical current @ 77 K, SF vs. soldering temperature 501-FS Temperature profile Despite of data scatter the trend is clearly seen

13. Critical current @ 77 K, SF vs. soldering time after t=200 C treatment 501-FS