Abstract
In order to optimize the conditions for residual stress measurement using a two-dimensional X-ray diffraction in terms of both efficiency and accuracy, the measurements were conducted on two specimens made of stainless steel in this study. The two specimens were treated by annealing and a cavitating jet in air so as to realize large grain and introduce residual stress. The specimens were oscillated in the ω- direction, representing a right-hand rotation of the specimen about the incident X-ray beam. The range of the oscillation, Δω, was varied and optimum Δω was determined. Moreover, combinations of the tilt angle between the specimen surface normal and the diffraction vector, ψ, with the rotation angle about its surface normal, φ, have been studied with a view to find the most optimum condition. The results show that the use of ω oscillations is an effective method for improving analysis accuracy, especially for large grain metals. The standard error rapidly decreased with increasing range of the co oscillation, especially for the annealed specimen which generated strong diffraction spots due to its large grain size.
