Exploring Inhomogeneous Residual Stress Fields Using the "Large Hole" Drilling Technique Combined with Digital Image Correlation

This study addresses the practical application of the digital image correlation method for experimental investigation of significantly inhomogeneous residual stress fields using the "large hole" drilling technique. Specially designed polymer material samples were used, in which a high-gradient residual stress field was created based on the approach proposed by the authors. Recommendations for optimal relationships between the diameter of the hole-indicator of residual stresses and the geometric parameters of the sample were developed based on the analysis of numerical modeling results of typical problems. The research results demonstrate the effectiveness of using the digital image correlation method and the authors' software for mathematical processing of tangential displacement fields to determine significantly inhomogeneous residual stress fields based on the "large hole" drilling method. The relative maximum deviation of residual stresses at characteristic points around the hole from their initial values does not exceed 4%, and the overall root-mean-square deviation is less than 7%.