本文將探討軸對稱雙壓電楔形結構之奇異性，包含兩個部分（1）以理論分析求解應力奇異性階數及角函數（2）應力及電位移強度因子之數值解。由於應力奇異性階數會受材料性質、楔形角和楔形邊界條件的影響。我們將利用複變函數配合特徵函數展開法分析軸對稱雙材料楔形結構之應力奇異性。在求得應力奇異性階數後就可利用有限元素法求得應力與電位移強度因子。
　　分析之接合楔形為壓電材料-壓電材料和壓電材料-導體材料兩種。由數值結果得知軸對稱之應力奇異性階數與廣義平面應變相等。利用有限元素法所逼近之應力奇異性階數與理論值比較，可判定有限元素網格的正確性，並配合已知的角函數求得應力及電位移強度因子。

　　This paper deals with the singular behaviors of an axisymmetric two-piezoelectric material wedge structure. It contains two parts (1) the theoretical determination of stress singularity order and the angular functions, and (2) the numerical solutions of generalized stress and electric displacement intensity factors. The stress singularity orders depending on the material properties, the wedge angle and wedge boundary conditions are obtained by employing the eigenfunction expansion method on complex potential function. After obtaining the singularity orders, the stress and electric displacement intensity factors are computed by using the finite element method.

　　Two cases studied in this paper are piezoelectric-piezoelectric and piezoelectric-conductor wedges. The results show that the singularity orders for the cases of general plane strain deformation and axisymmetric deformation are the same. The results of angular functions are shown graphically for a 900-900 axisymmetric wedge. After the finite element meshes are validated from the theoretical singularity order, the generalized intensity factors are computes by using the associated angular function.

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