A new method for the measurement of residual stresses in sheet materials is presented. The method is based upon the measurement of the curvature resulting from progressive removal of uniform layers from the surface of the specimen by chemical etching. The curvature is obtained from electronic speckle pattern interferograms (ESPI). As an illustration, a thin cold-rolled steel sheet was tested. Surface residual stresses were measured in as-received and heat-treated specimens. Results were found to be within the range given by x-ray diffraction measurements and show that annealing is an effective procedure for the reduction of residual stresses.
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