三層三次元異材接合体角部の特異応力場に対する接着層厚さの影響 : 外力が作用する場合

抄録

Influence of interlayer thickness on stress fields at a vertex in three-dimensional adhesive joints with three layers is evaluated using eigen analysis and boundary element method (BEM) using fundamental solutions for two-phase materials. A model for analysis is three-layered joints consisting of Si, resin and FR-4.5. A relationship between singular stress fields and the interlayer thickness is precisely investigated. All stress components are expressed in spherical coordinate systems in which origins are located at the vertex of each interface. Expression for stress, δ_<θθ>, near the vertex on the interface is firstly derived from the result of eigen analysis. The order of singularity for Si-resin interface is larger than that for resin-FR-4.5 interface. A coefficient of the power-law term in the stress expression for the distance from the vertex increases as resin thickness, the interlayer thickness, increases. The coefficient is demonstrated an upper limit when the resin thickness is larger than the width of the model. Value of coefficient in the power-law term of the angular function derived from BEM is a constant near that derived from eigen anlaysis for angular function on Si-resin interface. Three-dimensional intensity of singularity at the vertex of interface in three-dimensional joints is defined considering the intensities of singularity for radial direction and the angular function. Variation of the three-dimensional intensity of singularity at the vertex with the resin thickness is similar to that of the intensity of singularity for the radial direction.