Based on the principle of a Body Force Method (BFM), any inclusion problem can besolved only by using a Kelvin solution which corresponds to a stress field caused by a point forceacting in a homogeneous infinite plate, regardless of the mechanical properties of the inclusion. Thischaracteristic is true even for an anisotropic inclusion in which the number of independent elasticconstants are larger than that of a homogeneous material. In the present study, some problems among anisotropic inclusions were analyzed numerically to demonstrate the validity.

Residual stresses due to excessive internal pressure applied to an array of semi-circular surface notches is analyzed by body force method. The treated problem corresponds to a simple model of the Stealth Dicing (SD) which is expected as an alternative splitting technology applicable to brittle materials. In SD, laser beam of specific wave length is focused and scanned inside of the material to produce a SD-process zone which includes an array of microvoids. Each microvoid is thought to be received an excessive internal pressure due to thermal expansion and then material is split along a plane which contains an array of microvoids. After the mechanical splitting process, there expected to present a considerable residual stresses in the vicinity of an array of microvoids exposed at the splitting surface. In the present study, by analyzing the elastic-plastic stress fields near the array of surface microvoids, the mechanical characteristics of the SD induces surface is discussed.

In this study, an improved technique for the evaluation of stress intensity factor (SIF) along the 3D planar crack front is proposed. In the present analysis, a planar triangular element is used to cover the total crack face. The stress field induced by a body force doublet in an infinite body is used for a fundamental solution. In the present analysis, overall defined basic density function of body force doublet is introduced. The crack problem is formulated as hypersingular boundary integral equations and the magnitudes of distributed point force doublets are determined through boundary conditions. The numerical SIF solution obtained using the present approach was compared with the solution obtained using the conventional basic density function. The results indicate that the proposed technique improves the accuracy of SIF. In addition, some numerical examples were examined to verify the effectiveness and the robustness of the proposed technique.

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