Ⅱ型稳恒扩展裂纹尖端的奇异性场分析

ANALYSIS OF SINGULAR FIELD NEAR MODE Ⅱ STEADY PROPAGATING CRACK TIP

采用弹粘塑性力学模型代替通常的弹塑性模型 ,求得了不可压缩材料中Ⅱ型平面应变动态扩展裂纹尖端的指数奇异性场 ,并对不同的粘性系数和马赫数进行了数值计算 ,给出了应力场分布随粘性系数和马赫数的变化规律 .其结果不仅消除了弹塑性解中存在的塑性激波 ,而且当马赫数趋于零时便退化成准静态解 。

Presents the use of an elastic viscoplastic model instead of an ordinary elastic plastic one to obtain a power law singular tip field of mode Ⅱ moving crack of incompressible material under plane strain,and the numerical computations run at different viscosity coefficients and Mach numbers to establish the rules of stress field distribution,and concludes that not only the plastic shock in elastic plastic model is eliminated,the quasi static solutions are recovered when the Mach number approches zero.