Récents développements de la mesure des contraintes résiduelles par perçage incrémental

Abstract

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 enough developed to allow the use of the method for the measurement of residual stress distribution in the depth of a part. The method could only be used in the case of uniform stress state. New developments have shown that strains measured on the surface during an incremental drilling can be related to 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.Another problem of the method is the selection of the drilling technique. Two systems have been studied: ultra high-speed air-turbine and conventional milling machine.The sensitivity of the incremental hole-drilling method will be discussed. The new hole-drilling method has been applied to shot-peened as well as to water-quenched steel specimens. The results have been successfully compared with those of the bending-deflection and the X-ray diffraction methods.