研究Ⅰ型弹塑性界面裂纹问题。用傅里叶正、余弦变换及逐段定积分变换方法将边值问题的方程化为奇异积分方程组。解方程后计算了裂纹尖端塑性区尺寸及裂纹尖端张开位移COD ,给出了应变能释放率算式。结果表明 ,裂纹尖端塑性区尺寸和COD均仅与两种材料的较小屈服极限有关 ,较小屈服极限越大 ,则裂纹尖端塑性区尺寸和COD越小。 Study Ⅰ type elastic-plastic interface crack problem. The equations of boundary value problems are transformed into singular integral equations by means of Fourier positive and cosine transformations and piecewise definite integral transformations. After solving the equation, the plastic zone size at crack tip and the open displacement COD at crack tip are calculated, and the formula of strain energy release rate is given. The results show that the plastic zone size and COD of the crack tip are only related to the small yield limit of the two materials. The larger the smaller yield limit, the smaller the plastic zone size and COD of the crack tip.