METHOD FOR MEASURING CRITICAL CURRENT DENSITY OF HIGH-TEMPERATURE SUPERCONDUCTING CERAMIC SPECIMENS Russian patent published in 1998 - IPC

FIELD: measuring physical parameters of high-temperature superconducting materials. SUBSTANCE: four-probe method depending on measurement of transport current flowing through specimen at the moment of high-temperatures superconducting ceramic transfer from superconducting to resistive state is employed; specimen is placed in audio-frequency alternating magnetic field, critical transport current is measured, critical current as function of magnetic field strength is determined, and curve constructed is used to determine critical current density at zero magnetic field. This makes it possible to dispense with measurements in fields of intensity lower than 100 Oe where any increase of current through specimen may cause contact overheating and reduce measurement accuracy. EFFECT: improved measurement accuracy. 1 dwg