Metrological justification of reflection hologram interferometry with respect to residual stresses determination by means of blind hole drilling

Residual Stress Determination by Hole Drilling Combined with Optical Methods

“…For instance, Lobanov & Pivtorak [59,60] have described a compact, portable holographic system with a thermoplastic holocamera that could be installed on welded structures to find residual stresses by hole drilling. Pisarev et al [61][62][63] performed comprehensive holographic-hole drilling studies of residual stresses in both thin and thick walled welded aluminum plates, and in tubular specimens. Different methods for analyzing the information contained in holographic-hole drilling fringe patterns continue to be pursued [64][65][66].…”

General approach to residual stresses determination in thin-walled structures by combining the hole drilling method and reflection hologram interferometry

“…The latter circumstance is the essential condition for reliable deriving residual stress components from initial experimental data if small hole drilling serves for residual stress energy release [40][41][42]. Universally adopted approach to a decomposition of total stress field by membrane and bending components is based on Kirchgoff hypothesis, which assumes linear distributions of stress components in the normal to the surface direction [39]:…”

“…where matrix A represents by itself an explicit form of so-called transition model [40][41][42][43][44]. Such a model is a set of relations derived from mechanical formulation of the problem involved, which has also to include the material mechanical properties and the probe hole geometry.…”

“…Remarkable properties of reflection hologram interferometry with respect to residual stresses determination in plane structures by through or blind hole drilling have been previously established and comprehensively demonstrated [40][41][42]. Among them the unique capability of recognising principal strain directions at a stage of fringe patterns reconstruction is of great importance.…”

“…The third way for a choice and verification of the transition model is based on a constructing so-called reference fringe patterns of the second kind [43,44]. A fine coincidence between actual and reference interferograms takes place when the transition model involved corresponds to the type of residual stress field of interest [32][33][34][40][41][42]. If such a correlation is not achieved, the question on the accuracy of determination of residual stress components remains open.…”