Residual Stress Measurement using Neutron Diffraction

Abstract

Neutron diffraction is the only method which can measure residual stresses inside materials at centimeter-order depth nondestructively. Residual strains can be derived from the diffraction peak shift, and residual stresses can be calculated by applying lattice strains measured in three orthogonal directions to the Hooke’s law. In addition, the neutron diffraction method can be utilized for evaluation of deformation behaviors of engineering materials by measuring microstructural factors such as microstrains, texture and dislocation density. Therefore, the neutron diffraction technique is very useful in the design and development of engineering components, as well as in studies on materials engineering. Here we show the principle of the neutron stress measurement and the engineering neutron diffractometers as well as some applications.