Analysis of the Influence of the thickness and the hole radius on the calibration coefficients in the hole-drilling method for the determination of non-uniform residual stresses

Abstract

The Hole-Drilling method is a semi-destructive technique useful for obtaining residual stress distributions by drilling and measuring relieved strains. The standard for this method, i.e., ASTM E837 – 13a, is based on the Integral Method and facilitates obtaining the coefficient matrices required to solve the inverse problem and to calculate the residual stress at depths of up to 1.00 mm. A possible deviation from the coefficients given by this standard is searched when the piece has a small thickness or the hole diameter is not 2.00 mm. FEM simulations are performed with the aim of analysing these effects and proposing new matrices, expressions and correlations for conditions outside the usual thickness and diameter limits. A parametric sweep over a wide range of thicknesses and hole diameters has been implemented in ANSYS to establish a consistent and automated numerical procedure for widening the applicability of the Hole-Drilling method.