An investigation on the safe slitting interval in measuring the residual stresses

In the present paper, a novel approach based on the eigen-strain concept is presented to achieve the repeatability of the slitting experiment. A new parameter which specifies the residual stresses reduction zone was defined. Using this parameter, the proper distance of a new slit from the previous slit were calculated in order to diminish the effect of the previous one. Using the finite element simulation, it was illustrated that this interval eliminates the influence of the stress fileds of slits on each other. Eventually, four distinct slits were created on a four-point aluminum bending specimen that contained an identical eigen-strain distribution through the thickness. Elastic strains were measured at the strain gage location and the residual stresses were computed using the Tikhonov regularization. The results depicted that the proposed method is successful to determine the safe slitting intervals.