RECENTS DEVELOPPEMENTS DE LA MESURE DES CONTRAINTES RESIDUELLES PAR PERCAGE INCREMENTAL.

The hole-drilling method is widely used for the measurement of residual stresses in mechanical components. Until recent years, the experimental procedure and its theoretical background were not developed enough to allow the use of the method for the measurement of the residual stress distribution in the depth of a part. The method could only be used in the case of a uniform stress state. New developments have shown that strains measured on the surface during an incremental drilling can be related to the residual stress distribution. A finite element software has been developed by CETIM for the calculation of the coefficients of calibration of the hole drilling method. It is applicable to all isotropic materials, including multilayer materials. Two hole drilling systems have been studied: drilling with an ultrahigh-speed air turbine and drilling with a conventional milling machine. The sensitivity of the incremental hole-drilling method is discussed. The new hole-drilling method has been applied to both shot-peened and water-quenched steel specimens. The results have been successfully compared with those of the bending-deflection and X-ray diffraction methods.