Study on the Statistical Errors in X-Ray Stress Measurement with Two-Dimensional Detector

Abstract:

The sin² ψ method [1] is conventionally used well as how to measure non-destructively the residual strain and stress states of polycrystalline materials by X-ray diffraction. In the conventional method, there are Dölle-Hauk method [2] and Winholz-Cohen least squares analysis [3] as the determinations of the strain and stress states for limiting the influence of measurement errors. Many researches are made about the statistical error in those methods. In recent years, use of the X-ray stress measurements with two-dimensional detector from the conventional method is spreading. One of the measurements is called the cos α method. The measurement errors have attracted a great deal of attention for users as the spreads. Therefore, the basic equations and determinations of the strain and stress states are examined. The confidence intervals of measured stress by the cos α method. The research and development is performed for the the cos α method which took the influence of measurement errors into consideration.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 2373-2377
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.2373
• Online since: December 2018
• Authors: Shoichi Ejiri*, Hiroaki Ohba, Toshihiko Sasaki
• Keywords: Cos α Method, Internal Stress, Non-Destructive Inspection, Statistical Errors, Two-Dimensional Detector, X-Ray Stress Measurement

References

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