Development of the Hole-Drilling Method as Applied to the Study of Inhomogeneous Residual Stress Fields

A method of experimental and computational analysis of residual stress fields in flat parts based on mathematical processing of deformation response fields arising during drilling in the investigated area of a circular hole is proposed. In contrast to the classical method of drilling a hole, it is considered that there is a substantially inhomogeneous residual stress field in the area of the hole. For calculation of the residual stresses, a general solution obtained by N.I. Muskhelishvili for a two-dimensional problem of the theory of elasticity for a plate of unlimited dimensions with a circular hole, the contour of which is subjected to arbitrary normal and tangential loads, is used. The requirements for the accuracy and volume of the experimental data providing high accuracy of the results are established based on the numerical analysis (FEM) and experimental investigation using the flat optical model of the problem of a high-gradient (piecewise homogeneous) residual stress field.