An analytical model is introduced to analyse moving Griffith crack in a monoclinic crystalline layer of finite width and infinite extent with moving parallel punch pressure acting at the bounding surface of the layer because of the propagation of plane waves under mechanical point loading. Formulation of the model includes coupled singular integral equations with Cauchy‐type singularities. The expression of stress intensity factor (SIF) at the tip of moving crack having constant point loading is established in the closed‐form by employing Hilbert transformation. Further, expression of SIF is deduced for some particular cases of the crystalline layer, that is, without punch pressure and anisotropy. For the sake of validation, the obtained results are matched with pre‐established and standard results. Numerical computations and graphical demonstrations have been carried out for crystalline materials with monoclinic symmetry like lithium niobate and lithium tantalate and for isotropic material as well to unravel the effect of punch pressure, crack length, distinct positions of acting point load and the velocity of crack on SIF. Further, influence of anisotropy has been traced out remarkably through comparative study that is one of the pinnacles of the present study.

中文翻译：

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冲头压力作用下晶体单斜晶层中格里菲斯裂纹扩展引起的应力强度因子的分析研究

引入了一个分析模型来分析有限宽和无限范围的单斜晶体层中的移动格里菲斯裂缝，并且由于平面波在机械点载荷下的传播，移动的平行冲头压力作用在该层的边界面上。该模型的公式包括耦合的具有柯西型奇点的奇异积分方程。采用希尔伯特变换，在闭合形式下建立了具有恒定点荷载的运动裂纹尖端的应力强度因子（SIF）的表达式。此外，对于晶体层的某些特定情况，即没有冲压压力和各向异性，推导了SIF的表达。为了进行验证，将获得的结果与预先建立的标准结果进行匹配。已经对单斜晶对称的结晶材料（如铌酸锂和钽酸锂）以及各向同性材料进行了数值计算和图形演示，以揭示冲头压力，裂纹长度，作用点载荷的不同位置以及裂纹速度对材料的影响。 SIF。此外，各向异性的影响已经通过比较研究被显着地发现，该比较研究是本研究的顶峰之一。