1 Introduction
2 Background
2.1 Quantitative Tilt Fractography
2.2 Burgers Orientation Relationship and Parallelism of Slip Systems
3 Experimental Procedures
3.1 Materials
3.2 Fractography and Focused Ion Beam Methods
3.3 Scanning Electron Microscopy/EBSD
4 Results and Discussion
4.1 Fatigue Crack Initiation Site of Specimen 1
Feature | Unit Vector Describing Feature |
---|---|
Macroscopic fracture plane normal |
ab × bc = F = 0.4861i − 0.5205j + 0.7020k
|
Trace of step |
CG
1
= 0.5715i − 0.4719j − 0.7152k
|
Trace of step |
CG
2
= 0.5436i − 0.4282j − 0.7219k
|
Trace of step |
CG
3
= 0.5242i − 0.4996j − 0.6896k
|
Trace of β rib in facet plane |
β = 0.6969i − 0.3514j − 0.6252k
|
4.2 Fatigue Crack Initiation in Specimen 2
4.2.1 Effect of local crystallographic orientation on fatigue crack initiation
m′ | Slip Systems in Adjacent Colony | Adjacent Colony | Slip Systems in Reference Colony 5 | Angle/Axis Pair |
---|---|---|---|---|
0.98 |
\( \left( {10\bar{1}0} \right)\left[ {1\bar{2}10} \right] \)
| 1 | (0001) \( \left[ {\bar{1}2\bar{1}0} \right] \)
| 90 deg/\( \left\langle {1\;\overline{2.38} \;1.38\;0} \right\rangle \)
|
0.91 |
\( \left( {1\bar{1}01} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
|
\( \left( {0\bar{1}10} \right)\left[ {\bar{2}110} \right] \)
| ||
0.93 |
\( \left( {\bar{1}101} \right)\left[ {\bar{1}2\bar{1}\bar{3}} \right] \)
|
\( \left( {\bar{1}100} \right)\left[ {\bar{1}\bar{1}20} \right] \)
| ||
0.98 | (0001) \( \left[ {\bar{1}2\bar{1}0} \right] \)
|
\( \left( {10\bar{1}0} \right)\left[ {1\bar{2}10} \right] \)
| ||
0.93 | (0001) \( \left[ {2\bar{1}\bar{1}0} \right] \)
|
\( \left( {01\bar{1}1} \right)\left[ {\bar{1}2\bar{1}\bar{3}} \right] \)
| ||
0.92 |
\( \left( {\bar{1}100} \right)\left[ {\bar{1}\bar{1}20} \right] \)
|
\( \left( {0\bar{1}11} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
| ||
1.00 |
\( \left( {1\bar{1}01} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
| 3 | (0001) \( \left[ {11\bar{2}0} \right] \)
| 60.83 deg/\( \left\langle {\overline{1.377} \;\overline{1} \;2.377\;0.359} \right\rangle \)
|
0.90 |
\( \left( {1\bar{1}01} \right)\left[ {2\bar{1}\bar{1}\bar{3}} \right] \)
| (0001) \( \left[ {\bar{1}2\bar{1}0} \right] \)
| ||
0.97 | (0001)\( \left[ {2\bar{1}\bar{1}0} \right] \)
|
\( \left( {01\bar{1}1} \right)\left[ {\bar{1}2\bar{1}\bar{3}} \right] \)
| ||
0.93 | (0001) \( \left[ {\bar{1}2\bar{1}0} \right] \)
|
\( \left( {10\bar{1}1} \right)\left[ {11\bar{2}\bar{3}} \right] \)
| ||
0.98 |
\( \left( {\bar{1}101} \right)\left[ {\bar{1}2\bar{1}\bar{3}} \right] \)
|
\( \left( {0\bar{1}11} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
| ||
0.98 |
\( \left( {\bar{1}011} \right)\left[ {\bar{2}11\bar{3}} \right] \)
|
\( \left( {0\bar{1}11} \right)\left[ {\bar{1}\bar{1}2\bar{3}} \right] \)
| ||
0.94 |
\( \left( {10\bar{1}0} \right)\left[ {1\bar{2}10} \right] \)
|
\( \left( {10\bar{1}1} \right)\left[ {2\bar{1}\bar{1}\bar{3}} \right] \)
| ||
0.97 |
\( \left( {10\bar{1}1} \right)\left[ {11\bar{2}\bar{3}} \right] \)
| 4 | (0001)\( \left[ {2\bar{1}\bar{1}0} \right] \)
basal \( \left\langle {a_{2} } \right\rangle \)
| 60.83 deg/\( \left\langle {\overline{1.377} \;\overline{1} \;2.377\;0.359} \right\rangle \)
|
0.93 |
\( \left( {10\bar{1}1} \right)\left[ {2\bar{1}\bar{1}\bar{3}} \right] \)
| (0001) \( \left[ {\bar{1}2\bar{1}0} \right] \)
basal \( \left\langle {a_{3} } \right\rangle \)
| ||
0.93 |
\( \left( {0\bar{1}11} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
|
\( \left( {10\bar{1}0} \right)\left[ {1\bar{2}10} \right] \)
| ||
0.98 |
\( \left( {\bar{1}011} \right)\left[ {\bar{2}11\bar{3}} \right] \)
|
\( \left( {1\bar{1}01} \right)\left[ {2\bar{1}\bar{1}\bar{3}} \right] \)
| ||
0.98 |
\( \left( {\bar{1}011} \right)\left[ {\bar{1}\bar{1}2\bar{3}} \right] \)
|
\( \left( {1\bar{1}01} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
| ||
0.91 | (0001) \( \left[ {11\bar{2}0} \right] \)
|
\( \left( {\bar{1}011} \right)\left[ {\bar{2}11\bar{3}} \right] \)
| ||
1.00 | (0001)\( \left[ {2\bar{1}\bar{1}0} \right] \)
|
\( \left( {\bar{1}101} \right)\left[ {\bar{1}2\bar{1}\bar{3}} \right] \)
| ||
0.99 |
\( \left( {1\bar{1}01} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
| 6 | (0001) \( \left[ {11\bar{2}0} \right] \)
| 63.26 deg/\( \left\langle {\overline{10} \;5\;5\;3} \right\rangle \)
|
0.93 |
\( \left( {01\bar{1}1} \right)\left[ {11\bar{2}\bar{3}} \right] \)
|
\( \left( {10\bar{1}0} \right)\left[ {1\bar{2}10} \right] \)
| ||
0.98 | (0001)\( \left[ {2\bar{1}\bar{1}0} \right] \)
|
\( \left( {0\bar{1}11} \right)\left[ {\bar{1}\bar{1}2\bar{3}} \right] \)
| ||
0.92 |
\( \left( {\bar{1}101} \right)\left[ {\bar{1}2\bar{1}\bar{3}} \right] \)
|
\( \left( {0\bar{1}11} \right)\left[ {1\bar{2}1\bar{3}} \right] \)
| ||
0.94 |
\( \left( {\bar{1}011} \right)\left[ {\bar{2}11\bar{3}} \right] \)
|
\( \left( {0\bar{1}11} \right)\left[ {\bar{1}\bar{1}2\bar{3}} \right] \)
| ||
0.94 |
\( \left( {10\bar{1}0} \right)\left[ {1\bar{2}10} \right] \)
|
\( \left( {1\bar{1}01} \right)\left[ {2\bar{1}\bar{1}\bar{3}} \right] \)
| ||
0.96 to ~0.98 | all | 7 | all (see text for details) | 10.5 deg/[0001] |