Development of a miniature x-ray diffraction-based stress analysis system suitable for use on marine structures

摘要

Abstract: Neglect of residual stresses created during welding and forming processes can lead to stress corrosion cracking, distortion, fatigue cracking and premature failures in components. Accurate characterization of residual stresses in welds has been difficult and often impractical since most residual stress measurement techniques are destructive or lack the resolution to accurately characterize the steep stress gradients that exist in weld heat affected zones. The nondestructive nature of the x-ray diffraction technique and its ability to characterize severe stress gradients provided the inducement to develop an extremely portable stress analysis system. The Defense Research Establishment Atlantic and Proto Mfg. Ltd. embarked on a joint project to develop a truly portable stress analysis system which was suitable for use in the marine environment. This paper describes why x- ray diffraction was selected as the means of determining residual stress and provides a brief description of the technique, summarizes the result of the mXRD development and provides illustrations and performance results of some of its recent applications on marine structures. !5