降温速率对Ag-SmBCO单畴生长中自发成核的影响  

COOLING RATE ON SINGLE DOMAIN GROWTH OF Ag-SmBCO SPONTANEOUS NUCLEATION

作　　者：方华[1] 徐克西[1] 左鹏翔[1] 连博文[1] 曹越[1] 胡顺波[1] 

机构地区：[1]上海大学物理系,上海200444

出　　处：《低温物理学报》2012年第2期153-157,共5页Low Temperature Physical Letters

摘　　要：在前期的研究中曾通过Ag掺杂降低Sm123/Sm211体系熔点,利用Nd123冷籽晶技术成功制备出具有理想织构的SmBCO/Ag单畴块材.但在实验结果中发现相比于未掺杂坯体,掺入Ag后的SmBCO坯体生长速率下降,在所考察的慢冷温区里,生长速率呈不断减小趋势,最终因自发成核而无法继续生长,使得SmBCO单畴区域局限于15×15mm2范围内.为了抑制单畴生长中的自发成核现象,本文研究了降温速率对SmBCO/Ag单畴自发成核的影响.在两组不同条件下的降温速率实验中发现,不同的降温速率对体系自发成核的抑制效果是不同的.利用降低降温速率,成功地将掺Ag SmBCO单畴面积从15×15mm2增大至26×26mm2.In the previous study had decreased by Ag doping Sm123/Sm211 system melting point, using Nd123 seed technology of cold prepared successfully with the ideal texture SmBCO/Ag single domain bulk. However, compared with experimental results found in undoped adobe, adobe SmBCO after the incorporation of Ag growth rate decline in the study of the slow cooling temperature, the growth rate showed a decreasing trend, the end result of spontaneous nucleation and can not continue to grow, making SmBCO single domain area within the limited 15 ×15mm2. In order to restrain the growth in single-domain spontaneous nucleation phenomenon, this study of cooling rate on SmBCO/Ag single-domain spontaneous nucleation. In two different experiments under the conditions found in cooling rate, different cooling rates on the system, the inhibitory effect of spontaneous nucleation is different. Use of lower cooling rate,successfully doped Ag SmBCO single domain size froml5× 15mm2 increased to 26×26 mm2.

关 键 词：SmBCO/Ag单畴 自发成核 降温速率 

分 类 号：O782[理学—晶体学]