非定常局部熱発生近傍の微小き裂の熱応力拡大係数

stress intensity factors of a small crack have been analyzed when an infinite plate is step-functionally heated in a circular region near the crack tip. The stress solution can be obtained by superposing the stress disturbance by the crack on the transient thermal stresses due to the heat source in an infinite plate. The problem is reduced to a singular integral equation which satisfies the boundary condition on the crack face. The numerical results of stress intensity factors are obtained for the case of a uniformly distributed heat source. The effects of the location of the heat source on the variations of stress intensity factors are considered.