In Situ Stress Analysis under Dynamic State by Using X-ray Diffraction

射线应力分析是由平面间距的应变计算应力的方法，其值为实际应力。然而，目前大多数的X射线应力分析采用sin^2psi方法，该方法在每次测量中需要多个入射角来获得衍射角。因此，动应力环境下的测量尚未进行是真实的情况。本研究以实现动态条件下的实际应力观测为目的，拟采用X射线应力分析方法之一的“一次曝光技术”与“位敏正比计数器”相结合的方法来解决这一问题。SET法是一种测量同一入射X射线束在每psi角上的两个不同衍射角，并计算应力的方法，最适合动态条件下的实际应力测量。如果有必要同时计算两个衍射轮廓， ...更多信息 这就需要开发连接两个探测器的附件和系统。最初，我们计划使用X射线线性图像传感器，我们还开发了多功能X射线衍射仪，以连接各种探测器，并研究了每个探测器的特性。最后，由于两个线阵图像传感器难以计数，因此采用串联的PSPC解决了这一问题。其次，为了实现动态X射线应力分析，我们计划在旋转疲劳条件下进行X射线应力测量。首先，我们利用SET方法开发了X射线应力分析仪，并成功地观察到随着疲劳重复次数增加，实际应力的变化，使用带载荷计的旋转疲劳仪。提出了裂纹张开前实际应力随应力幅值的增大而减小，裂纹张开后由于裂纹表面应力的释放而减小并断裂的新观点。实验结果表明，X射线应力分析方法拓展了新的应用领域，对材料科学的下一步研究工作具有重要意义。少

The X-ray stress analysis is the method calculates the stress from strain of interplanner spacing, and the value is the actual stress. However, recently most of the X-ray stress analysis apply sin^2psi method which requires plural incident angles to get diffraction angle in each measurement. Therefore it is the real situation that the measurement under dynamic stress circumstances has not been carried out yet. This research is purposed on the realization of the actual stress observation under dynamic condition, it is planned to dissolve the problems by using the combination of "Single Exposure Technique", the one of the method for X-ray stress analysis, and "Position Sensitive Proportional Counter". SET is the method to measure two different diffraction angles in each psi angle from one incident X-ray beam, and to calculate the stress ; which is the most suitable to measure the actual stress under dynamic condition. Provided that it is necessary to count two diffraction profiles at onc … More e ; that causes necessity to develop the attachment and the system to connect two detectors. Originally, we planned to use an X-ray linear image sensor and also we developed the versatile X-ray diffractometer to attach various kinds of detectors and investigated the characteristics of each detector. Finally, it was too difficult to count with two linear image sensors, therefore we applied PSPC connected in series to dissolve the problem.Secondary, for the purpose to materialize the dynamic X-ray stress analysis, we planed X-ray stress measurement under rotational fatigue condition. At first, we developed X-ray stress analyzer utilizes SET method and succeeded to observe the actual stress change following to fatigue repetition increase by using cantilever-type rotational fatigue apparatus with loading gauge. It was made out newly that the actual stress before crack opening decreases with no relation to the stress amplitude, and after crack opening it decreases and breaks because of the stress releasing on the cracked surface. The result of our experience suggests to magnify the new applicable field for the X-ray stress analysis and contributes much to the next research work of material science. Less