抄録
The present study proposed a method to evaluate equibiaxial compressive residual stress of metal surface by means of depth-sensing indentation method with a spherical indenter. In particular, an inverse analysis using elastic-plastic finite element model for an indentation test was established to evaluate the residual stress from the indentation load-displacement curve. The proposed inverse analysis utilizes two indentation test results for a reference specimen whose residual stress is already known and for a target specimen whose residual stress is unknown, in order to exclude the effect of other unknown mechanical properties, such as Young's modulus and yield stress. The residual stress identified by using the indentation method is almost identical to that measured by X-ray diffraction, and the difference of the residual stress between these two methods ranges within 36 %, when the indentation loads are from 0.49 N to 0.98 N. Therefore, it can be concluded that the proposed method can effectively evaluate the residual stress on the metal surface.
