2004 年 53 巻 3Appendix 号 p. 21-25
For different rotationally symmetrical compressive residual stress distributions, typically found for shot peened steel surfaces, the reliability of the incremental hole drilling method is investigated by using the finite element code ABAQUS. Simulations of the hole drilling procedure were carried out in order to calculate strain relaxations at the surface due to the material removal with respect to the actual drilling depth. These calculated strain relaxation curves were evaluated by two different hole drilling evaluation methods, the integral method (IM) and the differential method (DM). The errors of the so called plasticity effect were determined by comparing the results of purely elastic simulations with those determined by elasto-plastic calculations. Obviously, the DM has principal difficulties in determining a residual stress gradient properly. The plasticity effect results for both methods in overestimated residual stress values in the surface near region.