Hi-value applications in compact fusion, electric aircraft engines and MRI are driving a renewed demand for HTS wires and tapes. Compact fusion in particular has the potential to drive the big push to the next level of current capacity, production capacity and production uniformity. An important need that remains to be met is an ability to verify the uniformity of current capacity over a very large quantity of tape required for a single device. Full in-line critical current characterisation can readily be provided only for 77 K performance, but it is well known that correlations between this data and the relevant data at lower temperature and moderate-to-high magnetic field is poor. Furthermore, the field-angle dependence of critical current can vary hugely between different manufacturers, yet is important information for magnet designers. Here we describe the “SuperCurrent” cryogen-free instrument that we have developed with capability to more-fully characterise short-section modern HTS tapes. Extensive temperature-, field- and angle-dependent data can be measured rapidly and automatically. We will show such data for a wide range of commercially available and developmental tapes with emphasis on details that are often overlooked such as n-values, angular hysteresis and 180° asymmetry.

Keywords: critical current, HTS tapes, anisotropy