Effect of sintering temperature under high pressure in the uperconductivity for MgB2

摘要

We report the effect of the sintering temperature on the superconductivity ofMgB2 pellets prepared under a high pressure of 3 GPa. The superconductingproperties of the non-heated MgB2 in this high pressure were poor. However, asthe sintering temperature increased, the superconducting properties were vastlyenhanced, which was shown by the narrow transition width for the resistivityand the low-field magnetizations. This shows that heat treatment under highpressure is essential to improve superconducting properties. These changes werefound to be closely related to changes in the surface morphology observed usingscanning electron microscopy.