低温物理学报
低溫物理學報
저온물이학보
CHINESE JOURNAL OF LOW TEMPERATURE PHYSICS
2007年
3期
167-172
,共6页
周克然%徐克西%刘建军%邱静和%吴兴达
週剋然%徐剋西%劉建軍%邱靜和%吳興達
주극연%서극서%류건군%구정화%오흥체
熔融织构Y1B2C3O7-δ%磁悬浮力%微裂纹和小孔%感应屏蔽电流环
鎔融織構Y1B2C3O7-δ%磁懸浮力%微裂紋和小孔%感應屏蔽電流環
용융직구Y1B2C3O7-δ%자현부력%미렬문화소공%감응병폐전류배
Melt textured Y1B2C3O7-δ%Levitation force%Microcracks and pore%ISCL
顶部籽晶熔融织构准单畴Y1B2C3O7-δ中磁悬浮力密度与籽晶位置的关系进行了深入研究.经研究发现在液氮温度下磁悬浮力密度大小随位置变化,在离顶部籽晶3 mm的地方达到最大值,换句话说就是在第二块薄片中具有最大磁悬浮力密度.这种现象可以用晶体生长和吸氧的过程的相互作用来解释.我们提出一个模型,在这个模型中Y211粒子的分布导致的小孔微结构降低了有效感应电流环的大小,从而相当于降低了单畴的有效尺寸,导致磁悬浮力的大小.从研究中发现纵向微裂纹对磁悬浮力的影响最为明显.这个结果对于顶部籽晶熔融织构准单畴的基础研究和制造有很大的意义.
頂部籽晶鎔融織構準單疇Y1B2C3O7-δ中磁懸浮力密度與籽晶位置的關繫進行瞭深入研究.經研究髮現在液氮溫度下磁懸浮力密度大小隨位置變化,在離頂部籽晶3 mm的地方達到最大值,換句話說就是在第二塊薄片中具有最大磁懸浮力密度.這種現象可以用晶體生長和吸氧的過程的相互作用來解釋.我們提齣一箇模型,在這箇模型中Y211粒子的分佈導緻的小孔微結構降低瞭有效感應電流環的大小,從而相噹于降低瞭單疇的有效呎吋,導緻磁懸浮力的大小.從研究中髮現縱嚮微裂紋對磁懸浮力的影響最為明顯.這箇結果對于頂部籽晶鎔融織構準單疇的基礎研究和製造有很大的意義.
정부자정용융직구준단주Y1B2C3O7-δ중자현부력밀도여자정위치적관계진행료심입연구.경연구발현재액담온도하자현부력밀도대소수위치변화,재리정부자정3 mm적지방체도최대치,환구화설취시재제이괴박편중구유최대자현부력밀도.저충현상가이용정체생장화흡양적과정적상호작용래해석.아문제출일개모형,재저개모형중Y211입자적분포도치적소공미결구강저료유효감응전류배적대소,종이상당우강저료단주적유효척촌,도치자현부력적대소.종연구중발현종향미렬문대자현부력적영향최위명현.저개결과대우정부자정용융직구준단주적기출연구화제조유흔대적의의.
The pellet homogeneity of levitation force vs. the position in comparison to the seed or to the top surface has been studied in the entire volume of a single domain Y1 B2C3O7- δ bulk sample processed by the Top-seeded Melt texturing growth (TSMTG). It is found that the levitation force increase and peak at a depth of 3 mm from the top of the sample at liquid nitrogen temperature. In other words, the second disk has the largest levitation force density. The phenomenon can be interpreted by the interaction between the microcracks or pores produced by crystal growth and the oxygenation. We propose a model in which Y211 particles distribution leading to microcracks and pores, therefore reduce the effective induced shielding current loops (ISCL) and increases the perimeters of ISCL, and thus this is corresponding to a decrease in the grain size, and thus result in greatly reduce levitation force in the bottom of the bulk.From the research, we know that the portrait microcracks of the YBCO bulk are also an important effect on the levitation properties. The result is very attractive and useful for TSMTG YBCO bulk fundamental studies and fabrication.