EDXRD Setup for Real Time Observation of a Gas Tungsten Arc (GTA) Welding Process
EDXRD Setup for Real Time Observation of a Gas Tungsten Arc (GTA) Welding Process
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用于实时观察钨极气体保护电弧 (GTA) 焊接过程的 EDXRD 设置
DOI：
10.4028/www.scientific.net/msf.706-709.1655
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
V. Honkimäki
中科院分区：
文献类型：
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作者：
J. Altenkirch;J. Gibmeier;T. Buslaps;V. Honkimäki
焊缝中的残余应力是工业部件结构完整性评估的主要关注点。使用成熟的破坏性或非破坏性技术可以相对简单地确定最终焊接中的应力。然而，此类测量仅反映最终条件，目前尚不清楚焊接过程中应力是如何产生的。为了优化焊缝中的最终残余应力，重要的是监测焊接过程中残余应变和应力的形成，从而深入了解应力发展的机制。在这项工作中，应用高计数率的非破坏性高能色散同步加速器 X 射线衍射，以便在时间和温度下原位溶解焊接过程。然而，常用仪器可实现的时间分辨率受到有限光子通量或探测器系统读出电子器件的限制，导致计数时间通常远长于 1 秒。我们展示了在 ESRF 的高通量和能量光束线 ID15A 上实现的能量色散探测器和读出电子装置。该设置允许以 5Hz 的采样率同时监测两个垂直方向的应变演变，从而获得足够的时间和温度分辨率。检测器死区时间的变化由校正函数解释，该校正函数是专门针对用于该原位实验的检测器设置而确定的。
Residual stresses in welds are of major concern for the structure integrity assessment in industrial components. The stresses in the final weld can be determined relatively simple using well established destructive or non-destructive techniques. However, such measurements reflect only the final condition and it remains unclear how stresses built up during the welding process. In order to optimise the final residual stresses in the weld, it is important to monitor the formation of residual strain and stress during the welding process and as such to gain insight into the mechanisms of stress development. In this work non-destructive high energy dispersive synchrotron X-ray diffraction at a high count rate is applied in order to dissolve the welding process in-situ in time and temperature. However, the achievable time resolution at commonly used instruments is restricted by either a limited photon flux or the read out electronics of the detector system resulting in counting times usually much longer than 1sec. We present an energy dispersive detector and read-out-electronics setup realized at the high flux and energy beam line ID15A at the ESRF. The setup allowed for monitoring the strain evolution in two perpendicular directions simultaneously at a sampling rate of 5Hz, resulting in sufficient time and temperature resolution. The change in detector dead time is accounted for by a correction function, which was specifically determined for the detector setup as used for this in-situ experiment.