Nondestructive measurement of residual stress in welded steel parts using digital image correlation method

In this paper, nondestructive measurement of residual stress in welded steel parts joint using digital image correlation method has been investigated. For this purpose, samples of A36 sheet were prepared and arc welding with shielding gas (GMAW) was performed on them. In order to measure nondestructive residual stress in all parts, digital image correlation method has been used. Base and welded samples with and without heat treatment have been evaluated with this method. The heat treatment of the samples is of the tempering type, which is performed in order to reduce the residual stress of the welded samples. In order to measure non-destructive residual stress, a new relationship has been introduced which is based on Hooke's law. Residual stress values are calculated by measuring the displacement and strain of the samples and placing their values in the given new relation. Examining the results, it has been found that the heat treatment performed on the samples has reduced the residual stress values by approximately 33% and the digital image correlation method has sufficient and appropriate accuracy for measuring nondestructive residual stresses.