An analysis of Lode effects in ductile failure
An analysis of Lode effects in ductile failure
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延性破坏中的洛德效应分析
DOI：
10.1016/j.jmps.2021.104468
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发表时间：
2021
影响因子：
5.3
通讯作者：
Benzerga, A.A.
中科院分区：
文献类型：
--
作者：
Torki, M.E.;Keralavarma, S.M.;Benzerga, A.A.
推导了多孔材料塑性的各向同性多表面模型，并用于研究第三应力不变量对延性破坏的影响。本构关系解释了包含随机分布的空隙的材料的均匀和非均匀屈服。各个空隙被建模为球形，但骨料没有净纹理。调用系综平均来操作从单空隙生长和合并的固有各向异性介观尺度过程到包含许多空隙的宏观体积的尺度过渡。相应地，在持续各向同性的约束下，有效产量和相关演化方程的表达式是从第一原理推导出来的。研究发现，对于足够平坦的空隙，静压轴上众所周知的顶点要么消失，要么对于细长的空隙发展成低阶奇点。当失效被视为不稳定的开始时，它总是在过渡到不均匀屈服之后发生，两者之间的延迟在很大程度上取决于洛德参数。研究发现，对于剪切主导的载荷，失效应变与 Lode 参数的关系较弱，但在所谓的广义拉伸或压缩状态附近则强烈依赖于该参数。根据新发现讨论了通过实验确定的近平面应力状态的断裂轨迹。
An isotropic multi-surface model of porous material plasticity is derived and employed to investigate the effects of the third stress invariant in ductile failure. The constitutive relation accounts for bothhomogeneousandinhomogeneousyielding of a material containing arandomdistribution of voids. Individual voids are modeled as spheroidal but the aggregate has no net texture. Ensemble averaging is invoked to operate a scale transition from the inherently anisotropic meso-scale process of single-void growth and coalescence to some macroscopic volume that contains many voids. Correspondingly, expressions for effective yield and associated evolution equations are derived from first principles, under the constraint ofpersistentisotropy. It is found that the well-known vertex on the hydrostatic axis either disappears for sufficiently flat voids or develops into a lower-order singularity for elongated ones. When failure is viewed as the onset of an instability, it invariably occurs after the transition to inhomogeneous yielding with the delay between the two depending strongly upon the Lode parameter. The strain to failure is found to be weakly dependent on the Lode parameter for shear-dominated loadings, but strongly dependent on it near states of so-called generalized tension or compression. Experimentally determined fracture loci for near plane stress states are discussed in light of the new findings.
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影响因子：
9.4
作者：
Pineau, A.;Benzerga, A. A.;Pardoen, T.
通讯作者：
Pardoen, T.
用于后定位分析的基于微力学的本构关系
影响因子：
1.9
作者：
M. Torki;A. A. Benzerga
通讯作者：
A. A. Benzerga
使用多表面耦合损伤塑性模型进行延性失效模拟
影响因子：
9.8
作者：
D. Reddi;V. K. Areej;S. M. Keralavarma
通讯作者：
S. M. Keralavarma
影响因子：
5.3
作者：
S. M. Keralavarma;D. Reddi;A. Benzerga
通讯作者：
S. M. Keralavarma;D. Reddi;A. Benzerga
任意载荷下多孔延性固体中空隙聚结的理论和数值分析
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
M. Torki;C. Tekoğlu;J. Leblond;A. Benzerga
通讯作者：
A. Benzerga