切欠き材の弾塑性応力およびひずみ集中係数

抄録

Elastic-plastic stress and strain concentration factors under tensile load have been examined for notched sheet, notched rectangular and circumferentially notched cylindrical specimens. For the notched sheet specimen the feature of variation of elastic-plastic stress and strain concentration factors obtained experimentally is similar to that calculated by the finite element method. The elastic stress distribution measured by using strain gages along the notch root of the rectangular specimen notched at two sides shows that both longitudinal and transverse stresses become maximum at the center of the notch root and decrease with approaching the end of the notch root. The state of stress at the notch root is biaxial tension. The elastic-plastic strain concentration factors computed by the finite element method for the rectangular specimen in plane strain state and the cylindrical one in axisymmetrical deformation increase rapidly with plastic deformation of the notch root but decrease rapidly to less than unity after the maximum value.