Interacting Effects Induced by Two Neighboring Pits Considering Relative Position Parameters and Pit Depth
Abstract
:1. Introduction
2. Finite Element Model
3. Results and Discussion
3.1. The Influence of the Relative Position Parameters
3.1.1. Two Intersecting Pits
3.1.2. Two Adjacent Pits
3.1.3. The Critical Corrosion Region
3.2. The Influence of Pit Depth
3.2.1. The Relationship between θth and Pit Depth
3.2.2. The Relationship between Ktnor and Pit Depth
4. Application
4.1. Estimation Procedure for the C-SCF
4.2. Application Example
5. Conclusions
- (1)
- For two intersecting pits, the combined SCF Ktcom increases with the increase of the relative position parameters θ and λ, and Ktcom always reaches its maximum at the symmetric location (θ = 90°) in the range of 0 < λ <1.
- (2)
- For two adjacent pits, the combined SCF Ktcom decreases with the increase of λ, and when λ > 2, the interacting effects have little contribution to the combined SCF, thus Ktcom ≈ Ktsin. The maximum C-SCF occurs at the asymmetric location of 60° ≤ θcri ≤ 90°. Meanwhile, θcri decreases with the increase of λ from 1 to 2, and θcri = 60° can be regarded as the limiting angle of this asymmetric feature.
- (3)
- The threshold angle θth exponentially decreases with the aspect ratio Rd (Equation (3)), which implies that the interacting effects induced by two neighboring pits exert influence in a larger scope for the deeper pits.
- (4)
- The normalized SCF generally increases with the pit depth, and follows a linear and an exponential relationship with Rd for two intersecting and adjacent pits, respectively. For the most disadvantageous configurations (i.e., the high stress concentration) of the relative position parameters, the empirical formulas (Equations (4) and (5)) are proposed to conservatively estimate the combined SCF and are validated via a practical example with the estimation error factor of 1.37.
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Definition | Pit 2 (μm) | ||
---|---|---|---|
Shallower | Identical | ||
Pit 1 (μm) | Shallow | Psh-Psh (d1 = 30, d2 = 16) | Psh-Pid (d1 = 30, d2 = 30) |
Hemi-spherical | Pse-Psh (d1 = 50, d2 = 30) | Pse-Pid (d1 = 50, d2 = 50) | |
Deep | Pde-Psh (d1 = 100, d2 = 50) | Pde-Pid (d1 = 100, d2 = 100) |
d (μm) | Rd | Ktsin | Ktnor | θ |
---|---|---|---|---|
15 | 0.3 | 1.53 | 1.051 | 86° |
1.047 | 85° | |||
30 | 0.6 | 1.76 | 1.05 | 55° |
50 | 1 | 2.06 | 1.05 | 45° |
80 | 1.6 | 2.37 | 1.057 | 36° |
1.033 | 35° | |||
100 | 2 | 2.51 | 1.05 | 30° |
150 | 3 | 2.72 | 1.051 | 27° |
1.048 | 26° | |||
200 | 4 | 2.82 | 1.052 | 22° |
1.046 | 21° |
d (μm) | Rd | Ktsin | Ktnor |
---|---|---|---|
30 | 0.6 | 1.76 | 1.49 |
50 | 1 | 2.06 | 2.03 |
80 | 1.6 | 2.37 | 2.98 |
100 | 2 | 2.51 | 3.64 |
150 | 3 | 2.72 | 5.33 |
200 | 4 | 2.82 | 7.062 |
d (μm) | Rd | Ktsin | Ktnor | θ |
---|---|---|---|---|
30 | 0.6 | 1.76 | 1.27 | 90° |
1.19 | 70° | |||
50 | 1 | 2.06 | 1.43 | 80° |
1.39 | 70° | |||
80 | 1.6 | 2.37 | 1.591 | 75° |
1.602 | 70° | |||
1.561 | 65° | |||
100 | 2 | 2.51 | 1.69 | 70° |
150 | 3 | 2.72 | 1.782 | 72° |
1.83 | 70° | |||
1.786 | 65° | |||
200 | 4 | 2.82 | 1.89 | 72° |
1.934 | 70° | |||
1.877 | 65° |
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Huang, Y.; Gang, T.; Chen, L. Interacting Effects Induced by Two Neighboring Pits Considering Relative Position Parameters and Pit Depth. Materials 2017, 10, 398. https://doi.org/10.3390/ma10040398
Huang Y, Gang T, Chen L. Interacting Effects Induced by Two Neighboring Pits Considering Relative Position Parameters and Pit Depth. Materials. 2017; 10(4):398. https://doi.org/10.3390/ma10040398
Chicago/Turabian StyleHuang, Yongfang, Tieqiang Gang, and Lijie Chen. 2017. "Interacting Effects Induced by Two Neighboring Pits Considering Relative Position Parameters and Pit Depth" Materials 10, no. 4: 398. https://doi.org/10.3390/ma10040398
APA StyleHuang, Y., Gang, T., & Chen, L. (2017). Interacting Effects Induced by Two Neighboring Pits Considering Relative Position Parameters and Pit Depth. Materials, 10(4), 398. https://doi.org/10.3390/ma10040398