MOD法制备YBCO高温超导带材缓冲层研究

发布时间：2018-03-20 21:10

  本文选题：MOD　切入点：氧化铈　出处：《电子科技大学》2010年硕士论文　论文类型：学位论文

【摘要】： 第二代高温超导带材YBa2Cu3O7-δ(YBCO)具有高的上临界磁场、高临界电流密度(Jc(T,H)104A/cm2,1T)、低交流损耗等优点,使其成为了高温超导材料的研究热点。由于工程应用的需要,二代超导带材需要制作在柔性基带上,为了解决直接在柔性金属基带上制备超导薄膜存在的基带易被氧化、金属与YBCO晶格失配度大等问题,需要在金属基带与超导层之间生长缓冲层。 在众多过渡层薄膜制备工艺中,金属有机物沉积(MOD)法可以精确控制薄膜的成分,不需要昂贵的真空系统,可实现连续化的工业生产。因此本文选用MOD法在具有双轴织构的镍钨合金(Ni-5at.%W)基带上分别制备了CeO2和La2Zr2O7两种非常有潜力的缓冲层薄膜,并研究了工艺条件对薄膜的结构和表面形貌的影响。 首先,本论文对制备CeO2的工艺条件进行了研究。通过对前驱液配制的大量研究,最终确定了以乙酰丙酮铈为溶质,冰乙酸为溶剂,在60℃下水浴30min,得到的前驱溶液稳定性较好。对前驱液浓度、旋涂参数、退火气氛、退火温度、升温速率、退火时间进行优化后,确定前驱液浓度为0.1M、甩胶速率4000rpm、甩胶时间30s,Ar+4%H2还原性气氛下,退火温度1000℃、快速退火、保温时间60min条件下所制备的CeO2薄膜具有(200)单一取向,面内外半高宽在6.0°以下,晶粒大小100nm左右,表面均方根粗糙度5nm左右。 然后,又对La2Zr2O7薄膜的制备工艺进行了研究。以乙酰丙酮锆和乙酰丙酮镧为溶质,丙酸为溶剂制备前驱液。优化工艺参数后确定前驱溶液阳离子总浓度为0.8M,甩胶速率4000rpm,甩胶时间30s,退火温度为940℃,保温时间为60min条件下所制备的La2Zr2O7薄膜具有(400)单一取向,面内外半高宽在6.0°左右,晶粒大小100nm左右,表面均方根粗糙度2nm左右。
[Abstract]:The second generation high temperature superconducting tape YBA _ 2Cu _ 3O _ 7- 未 YBCO) has the advantages of high supercritical magnetic field, high critical current density and low AC loss. The second generation superconducting tapes need to be fabricated on flexible substrates. In order to solve the problems such as easy oxidation of the subband and the mismatch between metal and YBCO lattice, the superconducting films prepared directly on the flexible metal substrates are easy to be oxidized. A buffer layer needs to be grown between the metal substrate and the superconducting layer. In the process of preparing transition layer films, the metal organic deposition (MOD) method can accurately control the composition of the films without the need for expensive vacuum systems. The continuous industrial production can be realized. Therefore, two kinds of CeO2 and La2Zr2O7 buffer layer thin films have been prepared by MOD method on Ni-W alloy Ni 5at. W) subband with biaxial texture, respectively. The effect of processing conditions on the structure and surface morphology of the films was studied. First of all, the preparation conditions of CeO2 were studied in this paper. Through a lot of research on the preparation of precursor solution, it was determined that cerium acetylacetone was used as solute and acetic acid as solvent. The precursor solution is stable at 60 鈩，

本文编号：1640815