Application of Energy Dispersive PNCCD Detector in Material Science using hard X-Rays
Application of Energy Dispersive PNCCD Detector in Material Science using hard X-Rays
复制标题
硬X射线能量色散PNCCD探测器在材料科学中的应用
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
U. Pietsch
中科院分区：
文献类型：
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作者：
N. Pashniak;A. Abboud;S. Send;B. Dönges;A. K. Hüsecken;H. Christ;U. Pietsch
pn结电荷耦合器件（pccd）是一种多功能探测器，它提供了利用白光x射线辐射进行能量色散x射线衍射（EDXD）实验的可能性。由于探测器区域的撞击点和光子事件的能量是同时测量的，因此EDXD允许样品表征而无需样品校准或耗时摇动样品，即样品可以通过“一次”曝光来表征。作为其在材料科学中应用的一个例子，我们展示了对双相不锈钢试样进行甚高周疲劳（VHCF）处理的EDXD实验。在5 - 40kev的能量范围内，可在数秒内实现探测试样的传输几何数据采集。由于样品的晶粒结构，出现了各种条状的Laue峰。洛厄条纹的强度和延伸随样品上位置的变化而变化。对劳厄条纹的内在结构进行了评价，发现沿劳厄条纹的能量随位置的变化而变化。然而，对于大多数检测到的劳埃条纹，它们的能量依赖遵循布拉格定律，在由VHCF处理形成的裂纹的空间位置发现了主要偏差。这使得EDXD方法适用于沿样品快速指示缺陷位置。
The pn-junction Charge Couple Device - pnCCD - is a versatile detector which offers the possibility to perform Energy-Dispersive X-ray Diffraction (EDXD) experiments using white Xray radiation. Because the point of impact on the detector area and the energy of a photon event is measured simultaneous EDXD allows for sample characterization without sample alignment or time-consuming rocking a sample, i.e. sample can be characterized by “one-shot” exposure. As an example for its application in material science we show an EDXD experiment performed at duplex stainless steel specimen treated by Very High Cycle Fatigue (VHCF). Probing the specimen in transmission geometry data acquisition could be realized within few seconds in an energy range between 5–40 keV. Due to the grain structure of sample various streaky Laue peaks appeared. Intensity and extension of the Laue streak varies as function of the position across the sample. Evaluating the intrinsic structure of Laue streaks it was found that the energy varies as position along the Laue streaks. Whereas for most of the detected Laue streaks their energy dependence follows Bragg´s law major deviations have been found at spatial positions of a crack formed due to VHCF treatment. This makes the EDXD method suitable for fast indication of defects positions along the sample.