Effect of Neutron Attenuation on Strain Measurement with Large Gauge Volume

Abstract

When measuring residual strain distributions of thick structural components such as thick butt-welds using neutron diffraction, it is required to make a gauge volume larger as well as to shorten neutron path length in a material to obtain sufficient diffraction intensity. In this study, neutron attenuation effect on the strain measurement with a large gauge volume was discussed on the normal strain measurement of a thick butt-weld. Influences of neutron attenuation like an apparent strain change were observed, and it was more noticeable when the gauge volume becomes larger. Therefore, the neutron attenuation effect should be considered in the strain measurement with a large gauge volume, and the neutron absorption corrections certainly play an important role for improvement of reliabilities of strain measurement using neutron diffraction with a large gauge volume.