摘要 |
PURPOSE:To attain the uniformity of oxygen deficiency concentration by using a composite oxide sintered body material containing at least Ba, Lu and Cu and sintering the material via specifying a thickness from the surface to the center thereof. CONSTITUTION:A powder mixture obtained by mixing each oxide or carbonate of Ba, Lu and Cu is used as raw powder and crushed after preliminary baking. This process is executed at least once or more. And baked body powder obtained therefrom is formed to such shape that a distance from the surface of a product after sintering to the center thereof is 1mm or less, or more preferably 0.5mm or less, and sintered. In this case, if the thickness of a material is small, reaction with the environment of sintering or heat treatment progresses over the whole of the material preferably for the superconducting characteristics thereof. The superconducting material available therefrom becomes an effective superconductor all over. Consequently, a high superconducting critical temperature Tc inherent to the material is embodied and it becomes possible even to increase real superconducting critical current density Jc. |