Abstract
A novel in situ scanning electron microscope (SEM) fatigue testing is proposed in this paper to investigate the fatigue crack growth mechanisms within one cyclic loading under plane stress conditions. The objectives of the experimental study are to verify the hypotheses of a small time scale fatigue crack growth model and to develop a new experimental methodology for the detailed mechanism investigation of fatigue crack growth. During the testing, one loading cycle is uniformly divided into a certain number of steps. At each step, high resolution images are taken around the crack tip region. Imaging analysis is used to quantify the crack growth kinetics and crack tip deformation behavior at any time instant in a loading cycle. Crack closure phenomenon is directly observed during the crack growth process in the current investigation. It is also observed that crack growth is not uniformly distributed within a loading cycle and only happens during a small portion of the loading path. Multiple mechanisms exist within one cyclic loading, which is not able to be captured using the classical cycle-based approaches. A detailed discussion is given based on the current investigation to explain some well-known issues in the classical fatigue theory.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 14-23 |
| Number of pages | 10 |
| Journal | International Journal of Fatigue |
| Volume | 42 |
| DOIs | |
| State | Published - Sep 2012 |
| Externally published | Yes |
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Keywords
- Crack closure
- Crack growth
- Fatigue
- In situ
- SEM
ASJC Scopus subject areas
- Industrial and Manufacturing Engineering
- Mechanical Engineering
- Mechanics of Materials
- Materials Science(all)
- Modeling and Simulation
Cite this
Investigation of incremental fatigue crack growth mechanisms using in situ SEM testing. / Zhang, Wei; Liu, Yongming.
In: International Journal of Fatigue, Vol. 42, 09.2012, p. 14-23.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Investigation of incremental fatigue crack growth mechanisms using in situ SEM testing
AU - Zhang, Wei
AU - Liu, Yongming
PY - 2012/9
Y1 - 2012/9
N2 - A novel in situ scanning electron microscope (SEM) fatigue testing is proposed in this paper to investigate the fatigue crack growth mechanisms within one cyclic loading under plane stress conditions. The objectives of the experimental study are to verify the hypotheses of a small time scale fatigue crack growth model and to develop a new experimental methodology for the detailed mechanism investigation of fatigue crack growth. During the testing, one loading cycle is uniformly divided into a certain number of steps. At each step, high resolution images are taken around the crack tip region. Imaging analysis is used to quantify the crack growth kinetics and crack tip deformation behavior at any time instant in a loading cycle. Crack closure phenomenon is directly observed during the crack growth process in the current investigation. It is also observed that crack growth is not uniformly distributed within a loading cycle and only happens during a small portion of the loading path. Multiple mechanisms exist within one cyclic loading, which is not able to be captured using the classical cycle-based approaches. A detailed discussion is given based on the current investigation to explain some well-known issues in the classical fatigue theory.
AB - A novel in situ scanning electron microscope (SEM) fatigue testing is proposed in this paper to investigate the fatigue crack growth mechanisms within one cyclic loading under plane stress conditions. The objectives of the experimental study are to verify the hypotheses of a small time scale fatigue crack growth model and to develop a new experimental methodology for the detailed mechanism investigation of fatigue crack growth. During the testing, one loading cycle is uniformly divided into a certain number of steps. At each step, high resolution images are taken around the crack tip region. Imaging analysis is used to quantify the crack growth kinetics and crack tip deformation behavior at any time instant in a loading cycle. Crack closure phenomenon is directly observed during the crack growth process in the current investigation. It is also observed that crack growth is not uniformly distributed within a loading cycle and only happens during a small portion of the loading path. Multiple mechanisms exist within one cyclic loading, which is not able to be captured using the classical cycle-based approaches. A detailed discussion is given based on the current investigation to explain some well-known issues in the classical fatigue theory.
KW - Crack closure
KW - Crack growth
KW - Fatigue
KW - In situ
KW - SEM
UR - http://www.scopus.com/inward/record.url?scp=84860385659&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84860385659&partnerID=8YFLogxK
U2 - 10.1016/j.ijfatigue.2011.03.004
DO - 10.1016/j.ijfatigue.2011.03.004
M3 - Article
AN - SCOPUS:84860385659
VL - 42
SP - 14
EP - 23
JO - International Journal of Fatigue
JF - International Journal of Fatigue
SN - 0142-1123
ER -