Analysis of clustering in Al-Mg-Si alloy by density spectrum analysis of atom probe data
Analysis of clustering in Al-Mg-Si alloy by density spectrum analysis of atom probe data
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DOI：
10.1016/j.ultramic.2010.11.022
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发表时间：
2011-05-01
期刊：
影响因子：
2.2
通讯作者：
Banhart, J.
中科院分区：
文献类型：
--
作者：
Wanderka, N.;Lazarev, N.;Banhart, J.
用原子探针层析技术研究了Al-Si-Mg合金团簇形成的早期阶段，并用一种新发展的基于最近邻分布的统计方法对其进行了评估。合金样品在固溶和淬火后自然时效一周。然后对镁、硅或镁-硅团簇的原子探针数据进行了分析。作为对比，还对沉淀物发达的人工时效样品进行了研究。建立了密度谱分析的一般方法，将问题归结为一个积分方程解。将该方法应用于原子探测器数据集，使我们能够探测星团并评估这些星团中的原子分数。这对于任意数量的成核相也是可能的。采用较高阶次近邻分布估计聚类大小。结合密度分布方法和蒙特卡罗模拟，我们发现了非常小的Si-Si和Mg-Mg团簇，其中只有很少的原子处于自然时效状态。(C)2010爱思唯尔B.V.保留所有权利。
Early stages of cluster formation in an Al-Si-Mg alloy were investigated by atom probe tomography and evaluated by a newly developed statistical method based on the nearest neighbour distributions. After solutionising and quenching, an alloy sample was naturally aged for one week. The atom probe data then measured was analysed for Mg, Si or Mg-Si clusters. For comparison specimen artificial aged with well developed precipitates was also investigated. A general approach for the analysis of density spectra was set up, which reduced the problem to the solution of an integral equation. Application of the method to the atom probe data set allowed us to detect clusters and to evaluate the atomic fractions within these clusters. This is also possible for an arbitrary number of nucleated phases. The higher-order next nearest neighbour distributions were used for the estimation of cluster sizes. Combining the density distribution method with a Monte Carlo simulation we found very small Si-Si and Mg-Mg clusters consisting of only a few atoms in the naturally aged state. (C) 2010 Elsevier B.V. All rights reserved.