Phase determination in dual phase steels via HREBSD‐based tetragonality mapping
Phase determination in dual phase steels via HREBSD‐based tetragonality mapping
复制标题
通过基于 HREBSD 的四方映射确定双相钢的相
DOI：
10.1111/jmi.12980
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发表时间：
2021
影响因子：
2
通讯作者：
Fullwood, David T.
中科院分区：
文献类型：
--
作者：
Adams, Derrik;Miles, Michael P.;Homer, Eric R.;Brown, Tyson;Mishra, Raj K.;Fullwood, David T.
电子背散射衍射（EBSD）是一种广泛使用的表征各种材料微观结构的方法。然而，使用标准EBSD软件难以准确区分钢中的相似（体心立方和体心四方，具有小的四方性）相。解决相位区分问题的一种方法是测量相位的四方性，这可以使用模拟图案和互相关技术来检测偏离完美立方晶格的失真。然而，在确定显微镜几何形状（所谓的图案或投影中心）时的小误差可能会导致四边形测量的重大误差，并导致错误的结果。本文采用了一种新的方法，通过应变最小化程序在大量的双相钢晶粒准确的图案中心的确定。然后生成四边形图，并用于识别相位和估计局部碳含量。该技术是使用动力学模拟和动态模拟模式，以确定其相对精度。与图像质量识别方法相比，基于逐点动态模拟图案和晶粒平均值比较的四边形图和后续相位图始终产生更精确和准确的结果，晶粒相位识别的准确度接近90%。四方性测量的误差似乎是1%的数量级，因此在碳含量估计中产生相当的~ 0.2%的误差。这样的误差使得该技术不适用于估计大多数商业钢的总碳含量，这些钢的碳含量通常低于0.1%。然而，即使在用于本研究的DP钢（0.1重量%）中，碳），它可以用来映射碳在较高的积累区域（如在马氏体与非均匀的碳含量）。Lay描述电子背散射衍射（EBSD）是一种广泛使用的方法，用于表征各种材料的微观结构。然而，由于晶体结构的微小差异，使用标准EBSD软件很难准确区分钢中的相似（BCC和BCT）相。解决相区分问题的一种方法是测量相的四方性，或晶格中的表观“应变”。这可以通过将实验EBSD图案与模拟图案通过互相关技术进行比较来完成，以检测远离完美立方晶格的失真。然而，在确定显微镜几何形状（所谓的图案或投影中心）时的小误差可能会导致四边形测量的重大误差，并导致错误的结果。本文采用了一种新的方法，通过应变最小化程序在大量的双相钢晶粒准确的图案中心的确定。然后生成四边形图，并用于识别相位和估计局部碳含量。该技术是使用简单的动力学模拟和更复杂的动态模拟模式，以确定其相对精度。与图像质量识别方法相比，基于逐点动态模拟图案和晶粒平均值比较的四边形图和后续相位图始终产生更精确和准确的结果，晶粒相位识别的准确度接近90%。四方性测量中的误差似乎是1%的量级，从而在碳含量估计中产生相应的误差。这样的错误...
Electron Backscatter Diffraction (EBSD) is a widely used approach for characterising the microstructure of various materials. However, it is difficult to accurately distinguish similar (body centred cubic and body centred tetragonal, with small tetragonality) phases in steels using standard EBSD software. One method to tackle the problem of phase distinction is to measure the tetragonality of the phases, which can be done using simulated patterns and cross‐correlation techniques to detect distortion away from a perfectly cubic crystal lattice. However, small errors in the determination of microscope geometry (the so‐called pattern or projection centre) can cause significant errors in tetragonality measurement and lead to erroneous results. This paper utilises a new approach for accurate pattern centre determination via a strain minimisation routine across a large number of grains in dual phase steels. Tetragonality maps are then produced and used to identify phase and estimate local carbon content. The technique is implemented using both kinetically simulated and dynamically simulated patterns to determine their relative accuracy. Tetragonality maps, and subsequent phase maps, based on dynamically simulated patterns in a point‐by‐point and grain average comparison are found to consistently produce more precise and accurate results, with close to 90% accuracy for grain phase identification, when compared with an image‐quality identification method. The error in tetragonality measurements appears to be of the order of 1%, thus producing a commensurate ∼0.2% error in carbon content estimation. Such an error makes the technique unsuitable for estimation of total carbon content of most commercial steels, which often have carbon levels below 0.1%. However, even in the DP steel for this study (0.1 wt.% carbon) it can be used to map carbon in regions with higher accumulation (such as in martensite with nonhomogeneous carbon content).Lay DescriptionElectron Backscatter Diffraction (EBSD) is a widely used approach for characterising the microstructure of various materials. However, it is difficult to accurately distinguish similar (BCC and BCT) phases in steels using standard EBSD software due to the small difference in crystal structure. One method to tackle the problem of phase distinction is to measure the tetragonality, or apparent ‘strain’ in the crystal lattice, of the phases. This can be done by comparing experimental EBSD patterns with simulated patterns via cross‐correlation techniques, to detect distortion away from a perfectly cubic crystal lattice. However, small errors in the determination of microscope geometry (the so‐called pattern or projection centre) can cause significant errors in tetragonality measurement and lead to erroneous results. This paper utilises a new approach for accurate pattern centre determination via a strain minimisation routine across a large number of grains in dual phase steels. Tetragonality maps are then produced and used to identify phase and estimate local carbon content. The technique is implemented using both simple kinetically simulated and more complex dynamically simulated patterns to determine their relative accuracy. Tetragonality maps, and subsequent phase maps, based on dynamically simulated patterns in a point‐by‐point and grain average comparison are found to consistently produce more precise and accurate results, with close to 90% accuracy for grain phase identification, when compared with an image‐quality identification method. The error in tetragonality measurements appears to be of the order of 1%, thus producing a commensurate error in carbon content estimation. Such an error …
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DOI：
10.1007/bf02642418
发表时间：
1982
期刊：
Metallurgical Transactions A
影响因子：
--
作者：
A. Marder
通讯作者：
A. Marder
DOI：
--
发表时间：
2016
期刊：
影响因子：
--
作者：
Tim Ruggles;S. Cluff;M. Miles;D. Fullwood;C. Daniels;Alex Avila;M. Chen
通讯作者：
M. Chen
使用微观表征和膨胀分析估计双相钢中的相分数
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
Jun;Seongjun Park;D. Suh;H. Han
通讯作者：
H. Han
Fe-C 马氏体钢中四方性的高角分辨率电子背散射衍射研究
影响因子：
2.8
作者：
Tomohito Tanaka;A. Wilkinson
通讯作者：
A. Wilkinson
DOI：
--
发表时间：
1989
期刊：
影响因子：
--
作者：
Huang;Gwo
通讯作者：
Gwo