Related Experiment Video
Updated: May 29, 2025
07:37
Full-field Strain Measurements for Microstructurally Small Fatigue Crack Propagation Using Digital Image Correlation Method
Published on: January 16, 2019
9.6K
Path differences between quasistatic and fatigue cracks in anisotropic media
Xinyuan Zhai1, Thomas Corre1,2, Ataollah Mesgarnejad3
1Institut Polytechnique de Paris, IMSIA, CNRS, EDF, ENSTA Paris, 91120 Palaiseau, France.
Physical Review. E
|February 7, 2025
Summary
Fatigue cracks in anisotropic media under cyclic loading differ significantly from quasistatic cracks. This study reveals loading symmetry dictates fatigue crack paths, unlike quasistatic cracks influenced by fracture energy anisotropy.
Area of Science:
- Materials Science
- Fracture Mechanics
- Solid Mechanics
Background:
- Anisotropic media exhibit direction-dependent material properties.
- Crack propagation behavior can differ under monotonic versus cyclic loading.
- Understanding crack path deviation is crucial for material design and failure analysis.
Purpose of the Study:
- To investigate and compare the crack path behavior of fatigue cracks under cyclic loading and quasistatic cracks under monotonic loading in anisotropic media.
- To determine the primary factors governing crack path selection in each loading regime.
- To develop a computational model that replicates observed experimental phenomena.
Main Methods:
- Experimental observation of crack propagation in anisotropic materials under controlled cyclic and monotonic loading conditions.
- Development and utilization of a computational model to simulate crack growth.
- Analysis of crack paths in relation to material anisotropy, fracture energy, and loading symmetry.
Main Results:
- Fatigue cracks under cyclic loading deviate significantly from quasistatic crack paths in anisotropic media.
- Quasistatic crack paths are primarily governed by the anisotropy of fracture energy.
- Fatigue crack paths are predominantly dictated by the symmetry of the applied loading, with microstructure playing a minor role.
Conclusions:
- A fundamental difference exists in crack path selection between fatigue and quasistatic loading in anisotropic materials.
- Loading symmetry is a dominant factor in fatigue crack propagation, overriding microstructural influences.
- These findings necessitate further research into the underlying failure mechanisms of fatigue cracks.
Related Concept Videos
01:21Fatigue
172
Fatigue occurs when materials rupture under repeated or fluctuating loads, even at stress levels far below their static breaking strength. It typically results in brittle failure, even for ductile materials. It is a critical consideration in designing machines and structural components subjected to repetitive or varying loads. The nature of these loadings can range from fluctuating loads like unbalanced pump impellers causing vibrations to repeatedly bending a thin steel rod wire back and forth...
172
01:15Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
246
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.
246
01:22Fatigue Strength of Concrete
162
Fatigue, in the context of materials science and engineering, refers to the weakening or failure of a material caused by repeatedly applied loads, even if these loads are below the strength limit of the material. Fatigue strength in concrete is a critical property that influences its durability and longevity. Concrete can fail in two ways due to fatigue. Static fatigue or creep rupture occurs under a constant load or one that increases slowly. The other failure mode is due to cyclical or...
162
01:23Behavior of Concrete Under Compressive Load
142
Concrete exhibits specific behaviors under different compressive loads. Understanding this is crucial for understanding its structural integrity. When concrete undergoes uniaxial compression, it tends to develop cracks that run parallel to the direction of the force. These parallel cracks stem from localized tensile stresses that occur perpendicular to the compression direction. Additionally, angled cracks may appear due to the formation of shear planes.
As the concrete specimen fractures under...
As the concrete specimen fractures under...
142
01:20Microcracking in Concrete
99
Microcracking in concrete refers to the tiny cracks that can form within the material even before any external load is applied. These microcracks typically occur at the interface between the coarse aggregate and the hydrated cement paste, often as a result of differential volume changes prompted by variations in stress-strain behavior, as well as thermal and moisture movement. Initially, these microcracks remain stable and do not grow substantially until the concrete is stressed to about 30...
99
01:15Stress: General Loading Conditions
299
To grasp the intricacy of real-world conditions where multiple loads are applied simultaneously to a structure, one might visualize a section passing through a specific point within a body, aligned parallel to the xy plane. This section is subjected to various forces, including original loads, normal forces, and shearing forces.
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes....
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes....
299