| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an oxide bulk superconductor very high in critical current density and trapped magnetic field and its preparation method. <P>SOLUTION: The superconductor is a (LRE, HRE)-Ba-Cu-O superconductor and has a structure comprising a superconductive phase and a particulate phase dispersed therein. The superconductive phase contains at least two rare earth elements represented by LRE and HRE and is represented by (LRE<SB>a</SB>, HRE<SB>1-a</SB>)<SB>1+x</SB>Ba<SB>2-x</SB>Cu<SB>3</SB>O<SB>y</SB>(wherein 0<a<1; 0≤x≤0.1; and 6.5≤y≤7.2). The particulate phase is represented by (LRE<SB>b</SB>, HRE<SB>1-b</SB>)<SB>2</SB>BaCuO<SB>5</SB>(wherein 0<b<1) or by (LRE<SB>c</SB>, HRE<SB>1-c</SB>)<SB>4-2z</SB>Ba<SB>2+2z</SB>Cu<SB>2-z</SB>O<SB>10-d</SB>(wherein 0≤c≤0.1; 0≤z≤0.1; and -0.5≤d≤0.5). Here, LRE means at least one element selected from among Gd, Eu, Sm, and Nd; and HRE means at least one element selected from among Yb, Er, Ho, Y, and Dy. The average particle size of the (LRE<SB>b</SB>, HRE<SB>1-b</SB>)<SB>2</SB>BaCuO<SB>5</SB>phase or of the (LRE<SB>c</SB>, HRE<SB>1-c</SB>)<SB>4-2z</SB>Ba<SB>2+2z</SB>Cu<SB>2-z</SB>O<SB>10-d</SB>phase is less than 1 μm. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
