论文标题
LEFM是在原子裂纹尖端产生的几何非线性的不可知论
LEFM is agnostic to geometrical nonlinearities arising at atomistic crack tips
论文作者
论文摘要
机械工程，材料科学等各种领域已经在连续规模上广泛使用线性弹性断裂力学（LEFM）。 LEFM也常规应用于原子量表。但是，其在此规模上的适用性仍然不那么良好，大多数研究都集中在非线性弹性效应上。使用离散晶格上最接近LEFM的谐波（捕捉弹簧）最近的邻居电位，我们表明原子晶格的离散性质会导致在能量最小化过程中偏离LEFM位移场。我们建议这些偏差可以归因于几何非线性，因为材料在断裂之前没有非线性弹性响应。我们证明，裂纹的前进和临界应力强度因子在增量载荷方案中受共同负载区域的控制，并且不能单独从属性（最大伸长率，最大持续力等）进行分析确定。
Various fields such as mechanical engineering, materials science, etc., have seen a widespread use of linear elastic fracture mechanics (LEFM) at the continuum scale. LEFM is also routinely applied to the atomic scale. However, its applicability at this scale remains less well studied, with most studies focusing on non-linear elastic effects. Using a harmonic (snapping spring) nearest-neighbor potential which provides the closest match to LEFM on a discrete lattice, we show that the discrete nature of an atomic lattice leads to deviations from the LEFM displacement field during energy minimization. We propose that these deviations can be ascribed to geometrical nonlinearities since the material does not have a nonlinear elastic response prior to bond breaking. We demonstrate that crack advance and the critical stress intensity factor in an incremental loading scenario is governed by the collectively loaded region, and can not be determined analytically from the properties (max. elongation, max. sustained force, etc.) of the stressed crack tip bond alone.
