Abstract—

Some features of the behavior of ideal tips of transverse shear and tear cracks (“shear-tear” crack tips) propagating together with the shear wave fronts are investigated. It is shown that in the quasi-static approximation, the ideally plastic behavior of the material near the tear crack has a spatial character and has characteristic planes oriented at an angle of 45 degrees to the directions of the principal stresses. This makes it possible to interpret the flow of material at the tip of a tear crack as sliding along the faces of regular polygonal pyramids with bases in the tear plane. The leading edge of a “shear-tear” crack, on which both tear and transverse shear occur, in the process of propagation degenerates either into the tip of a tear crack or into the tip of a transverse shear crack. This is due to the fact that the shear or tear of a smaller magnitude reaches its limiting value earlier (stops) and then the tip of the remaining type of crack propagates.

中文翻译：

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弹性粘塑性材料在运动裂纹尖端附近的动态变形特征

摘要-

研究了理想的横向剪切裂纹和撕裂裂纹尖端（“剪切撕裂”裂纹尖端）与剪切波前沿一起传播的行为特征。结果表明，在准静态近似中，撕裂附近材料的理想塑性行为具有空间特征，并具有与主应力方向成45度角定向的特征平面。这使得可以将撕裂裂纹尖端处的材料流解释为沿着在撕裂平面中具有底部的规则多边形金字塔的表面滑动。在扩展过程中，在其上同时发生撕裂和横向剪切的“剪切撕裂”裂纹的前边缘退化成撕裂裂纹的尖端或横向剪切裂纹的尖端。