Use of the hole-drilling method for measuring residual stresses in highly stressed shot-peened surfaces

The same shot-peening treatment was applied to five steels with different m echanical properties. The induced residual stress profiles were analyzed us ing X-ray diffraction and incremental hole drilling (IHD). The results of b oth techniques showed that IHD can still be successfully used for measuring shot-peening residual stresses, even if these exceed the yield strength of the bulk material. Expected errors due to the plasticity effect are reduce d by the strain hardening of the surface. For an assessment of the reliabil ity of IHD data, strain-hardening variation was quantified by microhardness measurements to estimate the yield strength of the plastified layer. All t he main calculation methods for IHD were applied. The results were compared and discussed with respect to the characteristics of each method.