Comparison of grain to grain orientation and stiffness mapping by spatially resolved acoustic spectroscopy and EBSD.
Comparison of grain to grain orientation and stiffness mapping by spatially resolved acoustic spectroscopy and EBSD.
复制标题
通过空间分辨声波谱和 EBSD 比较晶粒间的取向和刚度映射。
DOI：
10.1111/jmi.12550
复制
发表时间：
2017
影响因子：
2
通讯作者：
Mark AF
中科院分区：
文献类型：
--
作者：
Mark AF
我们的目标是通过将空间分辨声波谱 (SRAS) 与扫描电子显微镜内进行的电子背散射衍射 (EBSD) 方法进行比较，建立空间分辨声波谱 (SRAS) 在亚毫米到微米尺度上绘制晶粒取向和刚度各向异性的能力。前者通过测量弹性模量的空间变化来推断晶粒取向；相反，在 EBSD 中，弹性各向异性是从晶体取向的直接测量中推导出来的。这两个测试用例分别包括绘制厚电厂奥氏体钢和铁素体钢中大型 TIG 和 MMA 焊缝的熔合区；这些在技术上很重要，因为除其他外，弹性各向异性会导致超声波焊缝检测方法变得不准确，因为它会导致声波路径弯曲。 SRAS 的空间分辨率不如 EBSD（∼100 m vs.∼几 nm），角度分辨率也不如 EBSD（∼1.5° vs.∼0.5°）。然而，该方法可以应用于更大的区域（目前约为 300 平方毫米），速度更快（〜5 倍），更便宜且更容易执行，并且可以在制造车间进行。鉴于这些优势，特别是对于工业用户而言，以及该方法的不断改进，SRAS 有潜力成为取向映射的标准方法，特别是在弹性各向异性在宏观/组件长度尺度上很重要的情况下。
Our aim was to establish the capability of spatially resolved acoustic spectroscopy (SRAS) to map grain orientations and the anisotropy in stiffness at the sub‐mm to micron scale by comparing the method with electron backscatter diffraction (EBSD) undertaken within a scanning electron microscope. In the former the grain orientations are deduced by measuring the spatial variation in elastic modulus; conversely, in EBSD the elastic anisotropy is deduced from direct measurements of the crystal orientations. The two test‐cases comprise mapping the fusion zones for large TIG and MMA welds in thick power plant austenitic and ferritic steels, respectively; these are technologically important because, among other things, elastic anisotropy can cause ultrasonic weld inspection methods to become inaccurate because it causes bending in the paths of sound waves. The spatial resolution of SRAS is not as good as that for EBSD (∼100 m vs. ∼a few nm), nor is the angular resolution (∼1.5° vs. ∼0.5°). However the method can be applied to much larger areas (currently on the order of 300 mm square), is much faster (∼5 times), is cheaper and easier to perform, and it could be undertaken on the manufacturing floor. Given these advantages, particularly to industrial users, and the on‐going improvements to the method, SRAS has the potential to become a standard method for orientation mapping, particularly in cases where the elastic anisotropy is important over macroscopic/component length scales.