Quantitative nondestructive measurements of residual stresses

A stress maintained in the bulk of a material without application of an external traction (excluding gravity) or other sources, such as a thermal gradient, is called a residual stress. All residual stress systems have zero resultant force, the body being in equilibrium. The distance or range over which the stresses achieve this balance may be grouped into three classes as presented in Table 1. Also shown are the effects that the given examples exhibit using x-ray diffraction, the most popular technique to investigate residual stresses.