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

x射线应力分析是根据规划间距的应变计算应力的方法，其值为实际应力。然而，目前的x射线应力分析大多采用sin^2psi方法，每次测量都需要多个入射角才能得到衍射角。因此，在动应力情况下的测量尚未进行，这是实际情况。本研究以实现动态条件下的实际应力观测为目标，拟将x射线应力分析方法之一的“单曝光技术”与“位置敏感比例计数器”相结合，解决这一问题。SET是测量入射x射线在每个psi角下的两个不同衍射角，并计算应力的方法；这种方法最适合测量动态条件下的实际应力。假定有必要同时计算两个衍射剖面……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，并开发了多功能x射线衍射仪，用于附加各种探测器，并研究了每种探测器的特性。最后，由于两个线性图像传感器难以计数，因此我们采用串联PSPC来解决这个问题。其次，为了实现动态x射线应力分析，我们规划了旋转疲劳条件下的x射线应力测量。首先，利用SET方法研制了x射线应力分析仪，并利用带加载计的悬臂式旋转疲劳仪成功地观察了疲劳重复次数增加后的实际应力变化。新发现裂纹开启前的实际应力减小与应力幅值无关，而裂纹开启后由于裂纹表面的应力释放，实际应力减小并破裂。研究结果为x射线应力分析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