Quantification of dislocation structure heterogeneity in deformed polycrystals by EBSD
Quantification of dislocation structure heterogeneity in deformed polycrystals by EBSD
复制标题
DOI：
10.1088/0965-0393/20/2/024007
复制
发表时间：
2012-03-01
影响因子：
1.8
通讯作者：
Wagner, F.
中科院分区：
文献类型：
--
作者：
Field, D. P.;Merriman, C. C.;Wagner, F.
多晶材料的塑性变形涉及位错与晶格缺陷的复杂相互作用。位错密度的几何必要成分可以在一定程度上量化，使用目前可用的三维成像技术，从平面区域或体积上的自动电子后向散射衍射扫描获得的数据。可靠的测量要求用于确定几何上必要的位错密度的取向数据的步长与微观结构信息的尺度一致。对变形的铜、铝和钢试样进行了测量。在压缩变形10%的Cu中，几何上必需的位错密度约为总体估计位错密度的15-30%。人工智能中的测量表明，在相同的结构上，三维估计值大约是二维测量值的1.2-2倍。对间隙自由钢试样的分析表明，变形至12%拉伸变形伸长率时，平均几何必要位错密度增加了一个数量级。
Plastic deformation in polycrystalline materials involves a complex interaction of dislocations with defects in the lattice. The geometrically necessary component of the dislocation density can be quantified to some extent using data obtained from automated electron backscatter diffraction scans over planar regions or volumes using the three-dimensional imaging techniques that are currently available. Reliable measurements require that the step size of the orientation data used in determination of geometrically necessary dislocation densities be on the scale of the microstructural information. Measurements were performed in deformed Cu, Al and steel specimens. Geometrically necessary dislocation density in Cu deformed 10% in compression was about 15-30% of the overall estimated dislocation density. Measurements in Al demonstrate that three-dimensional estimates are on the order of 1.2-2 times the values obtained from 2D measurements on the same structures. Analysis of interstitial free steel specimens shows an increase in average geometrically necessary dislocation density by an order of magnitude for specimens deformed to 12% tensile deformation elongation.