The image contrast of sheared needle-like β'' precipitates in the Al-Mg-Si alloy system is investigated with respect to shear-plane positions, the number of shear-planes, and the active matrix slip systems through multislice transmission electron microscopy image simulations and the frozen phonon approximation. It is found that ADF STEM images are mostly affected by shear-planes within a distance ∼ 6-18 unit cells from the specimen surface, while about 5-10 equidistant shear-planes are required to produce clear differences in HRTEM images. The contrast of the images is affected by the Burgers vector of the slip, but not the slip plane. The simulation results are discussed and compared to experimental data. This article is protected by copyright. All rights reserved.

中文翻译：

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Al-Mg-Si合金中剪切针状析出物的多切片图像模拟

通过多层透射电子显微镜图像研究了Al-Mg-Si合金系统中剪切针状β''析出物在剪切面位置、剪切面数量和有源基体滑移系统方面的图像对比度模拟和冻结声子近似。发现 ADF STEM 图像主要受距离样品表面约 6-18 个单位单元内的剪切平面的影响，而需要大约 5-10 个等距剪切平面才能在 HRTEM 图像中产生明显差异。图像的对比度受滑移的 Burgers 矢量影响，但不受滑移平面的影响。讨论了模拟结果并与实验数据进行了比较。本文受版权保护。版权所有。