EBSD入门简介-姚宗勇.ppt

* * * 因为在单晶上制备的YBCO薄膜可获得双轴织构，得到较高Jc，所以基于这种个思路，科学家用外延生长的方法，将YBCO系超导体沉积在有双轴织构的多晶样品上，制备YBCO的柔性带材，这样可以在实际中应用。要制备即具有高Jc，也要可应用于实际的超导代词， 其中轧制辅助沉积工艺（RABiTS）工艺大规模生产可行性高，所以是很有前途的制备工艺。 示意图中所示是覆膜导体的组成示意图。 最下面是具有双轴织构的金属基底，它还同时提供机械强度方面的支撑作用，金属基底上生长具有双轴织构的缓冲层，其主要作用是防止金属对YBCO的扩散，影响超导性能。在缓冲层上面生长具有双轴织构的超导薄膜。这种层状结构的导体也称覆膜导体。 其中，金属基底的双轴织构对于轧制金属来说就是立方织构即轧面法向//[001]，轧向//[100]。 Fcc金属在经过大变形量轧制后进行高温退火可以得到很强的立方织构，同时，金属镍的热膨胀系数与晶格常数与后续的缓冲层和YBCO匹配较好，利用这些特点，选用金属镍作为基底材料。 * * * * Different crystal orientations produce different Kikuchi patterns. Imagine the grey background as the sample surface and the green a cubic crystal unit cell, in this case of Si. In the first picture the (100) crystal plane is shown parallel to the sample surface, with the viewer looking straight down on the sample, i.e. straight down the 100 direction. The simulated Kikuchi pattern is shown below. If the crystal were rotated around its 100 axis by 45deg it would look like the second picture. The simulated Kikuchi pattern rotates in lock step with the crystal. You can try this at home with a piece of single crystal Si – just rotate it using the SEM stage control. If you then rotate the crystal up 45 deg you would be looking at the (110) plane (or straight down the 110 direction). If you then rotate the crystal about its 100 axis again by 45 deg you will be looking straight down the 111 axis and at the (111) plane. * Remember a 2d pattern comes from a single spot mode data acquisition on the sample. Thus, to cover an area of interest on a sample requires automatic beam movement, and/or stage movement. * Remember a 2d pattern comes from a single spot mode data acquisition on the sample. Thus, to cover an area of interest on a sample requires automatic beam movement, and/or stage movement. * * * */93 2008年1月10日 不同晶体取向对应不同的菊池花样 通过分析EBSP花样我们可以反过来推出电子束照射点的晶体学取向 (100) (100) (110) (111) */93 2008年1月10日 EBSD如何工作? */93 2008年1月10日 图像处理及菊池带识别 采集花样 与数据库进行相及取向的对比 校对并给出标定结果 输出相及取向结果 一个完整的标定过程 取点 */93 2008年1月10日 多点自动标定过程 Collected EBSP