Residual Stresses Measurements in Plates by Electrochemical Machining of Fine Layers

Plastic deformation treatments of hardened metallurgical products are becoming an usual technique of industries which transform semi-finisched products. They are now used systematically in residual stresses relaxation. To determine the residual stresses distribution within the material thickness, we have developed the method which uses fine layers removal. The first part of this paper describes a method of calculation and measurement to evaluate residual stresses in stainless steel plates. Also introduced is the electrochemical technique used: machining and tooling devices, electrolyte, working conditions, measurement processes, which do not induce additional stresses. Then we submit our results, obtained from several stainless steel plates, previously hyper-quenched and then either worked by tensioning, or straightened with leveling rolls.