References
B.8.1 AW guidance on assessment of the fitness for purpose of welded structures. IIW Draft for Development doc. SST-1157-90.
B.8.2 Guidance on some methods for the derivation of acceptance levels for detects in fusion welded joints. British Standard Published Document 6493:1991.
B.8.3 Standard test method for measurement of fatigue crac k growth rates, ASTM E647-93.
B.8.4 Fatigue crack propagation in aluminium, IIW Document XIII-B77-90.
B.8.5 Stress intensity factor equations for cracks in three-dimensional finite bodies. ASTM STP 791, 1983, ppI-238-1-265.
B.8.6 Graf, U: 'Fracture mechanics parameters and procedures for the fatigue behaviour estimation of welded aluminium components1, 1992.
B8.7" Simulations of short crack and other low closure loading conditions utilising contact Kmax AK-decreasing fatigue crack growth procedures. ASTM STP 1149-1992, pp.197-220.
a) Wrought aluminium alloys Upperbound fatigue crack growth data from tables B.2 |
¡.3 and B3.5. | |||
Stress Range |
Uniform Tension |
Kt=3.0, Dt=2.0mm, DCF5] | ||
Stress intensity ratio R: |
0,1 |
0,8 |
0,1 |
0,8 |
N/mm2 |
mm |
mm |
mm |
mm |
16 |
8,57 |
6,68 |
6,28 |
4,06 |
20 |
6,63 |
4,79 |
4,00 |
1,99 |
25 |
4,82 |
3,00 |
2,19 |
0,266 |
25" |
- |
- |
0,11 |
0,11 |
31 |
3,22 |
1,42 |
0,44 |
0,07 |
31i) |
- |
1,42 |
0,051 |
0,051 |
39i) |
1,24 |
0,52 |
0,025 |
0,025 |
49" |
0,30 |
0,26 |
0,014 |
0,014 |
62" |
0,14 |
0,13 |
0,0073 |
0,0073 |
77" |
0,078 |
0,075 |
- |
- |
96" |
0,042 |
0,042 |
- |
- |
121" |
0,023 |
0,023 |
- |
- |
Note 1: FCGR: WAA K^ thickness of 12mm |
„ 10MPa(m)°'5 one |
single phase, i.e. FCG from a; up to the plate |
b) Cast aluminium alloys Upperbound fatigue crack growth rate from table BJ.^ |
• | |||
Stress Range |
Uniform Tension |
K,=3.0, Dt=2.0mm, DCF5] | ||
Stress intensity ratio R: |
0,1 |
0,8 |
0,1 |
0,8 |
N/mm2 |
mm |
mm |
mm |
mm |
16 |
11,99 |
6,46 |
11,99 |
3,33 |
20 |
11,88 |
4,49 |
11,56 |
1,83 |
25 |
10,99 |
2,97 |
9,09 |
0,391 |
31 |
8,87 |
1,92 |
5,90 |
0,200 |
39 |
6,51 |
1,17 |
3,32 |
0,1067 |
49 |
4,48 |
0,71 |
0,072 |
0,062 |
62 |
2,86 |
0,42 |
0,036 |
0,035 |
77" |
1,80 |
- |
- |
- |
77 |
0,295 |
0,259 |
0,022 |
0,0219 |
96" |
1,082 |
- |
- |
- |
96 |
0,162 |
0,159 |
- |
- |
121" |
0,621 |
- |
- |
- |
121 |
0,096 |
0,095 |
- |
- |
Note 1: FCGR CAA R constant, R = 0,1,1 single phase, ie FCG from a, up to the plate thickness of 12mm |
Table B.7.2 Fatigue life predictions based on upperbound fatigue crack growth data for wrought aluminium alloys from tables B .3.3 and B3.5
a) Uniform tension - Phase 2 | ||||||
Type of FCGR: |
R=Kmm/Kmax = constant |
Kmax = 10MPa(m)°'5 constant | ||||
Stress intensity ratio R: |
0,1 |
0,8 |
0,1 |
0,8 | ||
Crack |
Stress |
Fatigue |
Fatigue |
Fatigue |
Fatigue | |
length, |
intensity |
life, |
life, |
life, |
life | |
ai |
range, | |||||
mm |
MPam0,5 |
cycles |
cycles |
cycles |
cycles | |
12,00 |
13,88 |
- |
- |
- |
- | |
11,00 |
12,97 |
1 428 |
3 |
1 411 |
2 | |
10,00 |
12,03 |
3 172 |
8 |
3 131 |
6 | |
9,00 |
11,08 |
5 347 |
17 |
5 271 |
15 | |
8,00 |
10,12 |
8 123 |
37 |
7 996 |
40 | |
7,00 |
9,16 |
11 749 |
80 |
11 545 |
110 | |
6,00 |
8,20 |
16 614 |
185 |
16 293 |
336 | |
5,00 |
7,25 |
23 258 |
464 |
22 854 |
1 |
163 |
4,00 |
6,30 |
33 728 |
1 312 |
32 319 |
4 |
295 |
3,00 |
5,31 |
61 317 |
3 452 |
46 887 |
12 |
007 |
2,00 |
4,25 |
149 999 |
16 791 |
71 997 |
33 |
860 |
b) Stress gradient - Phase 2 | ||||||
Type of FCGR: |
R Kmin/ICmax |
= constant |
Kmax= 10MPa(m)°'5 |
constant | ||
Stress intensity ratio R: |
0,1 |
0,8 |
0,1 |
0,8 | ||
Crack |
Stress |
Fatigue |
Fatigue |
Fatigue |
Fatigue | |
length, |
Intensity |
life, |
life, |
life, |
life, | |
Range, | ||||||
mm |
MPam05 |
cycles |
cycles |
cycles |
cycles | |
12,00 |
15,61 |
- |
- |
- |
- | |
10,00 |
14,65 |
2 027 |
2 |
2 009 |
1 | |
9,00 |
14,00 |
3 214 |
3 |
3 184 |
2 | |
8,00 |
13,26 |
4 580 |
6 |
4 535 |
3 | |
7,00 |
12,42 |
6 196 |
10 |
6 130 |
6 | |
6,00 |
11,51 |
8 166 |
17 |
8 070 |
12 | |
5,00 |
10,51 |
10 655 |
31 |
10516 |
28 | |
4,00 |
98,42 |
13 950 |
64 |
13 745 |
77 | |
3,00 |
8,19 |
18618 |
158 |
18 303 |
275 | |
2,00 |
6,72 |
26 049 |
547 |
25 524 |
1 590 |
Table B.73. Fatigue life predictions based on upperbound fatigue crack growth data for cast aluminium alloys from table B3.4 and wrought alloy AA 6005A-T6 from table 8.3.2(a)
a) Uniform tension - Phase 2 | ||||||||
Type of FCGR: |
CAA R-Kmin/Kmax — |
constant |
AA6005A R=Kmii/Kmax = |
constant | ||||
Stress intensity ratio R: |
0,1 |
0,8 |
0,1 |
0,8 | ||||
Crack |
Stress |
Fatigue |
Fatigue |
Fatigue |
Fatigue | |||
length, |
intensify |
life, |
life, |
life, |
life | |||
a¡ |
range, |
cycles | ||||||
mm |
MPam0'5 |
cycles |
cycles |
cycles | ||||
12,00 |
13,88 |
- |
- |
- |
- | |||
11,00 |
12,97 |
2'016 |
0 |
2 725 |
11 | |||
10,00 |
12,03 |
4'670 |
0 |
6 092 |
47 | |||
9,00 |
11,08 |
8'267 |
0 |
10 346 |
172 | |||
8,00 |
10,12 |
13'294 |
1 |
15 849 |
681 | |||
7,00 |
9,16 |
20*552 |
4 |
23 148 |
3 031 | |||
6,00 |
8,20 |
32*302 |
16 |
33 107 |
8 369 | |||
5,00 |
7,25 |
57*146 |
63 |
50 251 |
16 049 | |||
4,00 |
6,30 |
116*025 |
312 |
96452 |
27 648 | |||
3,00 |
5,31 |
279'046 |
1*692 |
246958 |
46 490 | |||
2,00 |
4,25 |
938*072 |
6*154 |
997 170 |
83 056 |
b) Stress gradient - Phase 2 | ||||||||
Type of FCGR: |
CAA R=Kmin/Kmax = constant |
AA6005A R=Kmin/Kin„ |
= constant | |||||
Stress intensity ratio R: |
0.1 |
0.8 |
0.1 |
0.8 | ||||
Crack |
Stress |
Fatigue |
Fatigue |
Fatigue |
Fatigue | |||
length, |
intensity |
life, |
life, |
life, |
life, | |||
a¡ |
range, | |||||||
mm |
MPam0,5 |
cycles |
cycles |
cycles |
cycles | |||
12,00 |
15,61 |
- |
- |
- |
- | |||
11,00 |
15,19 |
1 182 |
0 |
1 808 |
1 | |||
10,00 |
14,65 |
2517 |
0 |
3 793 |
3 | |||
9,00 |
14,00 |
4 081 |
0 |
6 035 |
7 | |||
8,00 |
13,26 |
5 978 |
0 |
8 636 |
16 | |||
7,00 |
12,42 |
8 367 |
0 |
11 742 |
38 | |||
6,00 |
11,51 |
11 505 |
0 |
15 572 |
109 | |||
5,00 |
10,51 |
15 835 |
1 |
20477 |
383 | |||
4,00 |
9,42 |
22 202 |
3 |
27 074 |
1 776 | |||
3,00 |
8,19 |
33 164 |
13 |
36 609 |
6 769 | |||
2,00 |
6,74 |
64 980 |
94 |
59496 |
15 333 |
Table B.7.4. Fatigue life predictions based on upperbound fatigue crack growth data for wrought aluminium alloys from table B.3.3. and wrought alloy AA 6005A-T6 from table B.3.2.(b)
a) Uniform tension - Phase 1 | |||||
Type of FCGR: |
WAA Kmax 10MPa(m)°'5 const. |
AA6005A K,,^ 10MPa(m)0-5 constant | |||
Stress intensity ratio R: |
0,1 |
0,8 |
0,1 |
0,8 | |
Crack |
Stress |
Fatigue |
Fatigue |
Fatigue |
Fatigue |
length, |
intensity |
life, |
life |
life, |
life, |
ai |
range, | ||||
mm |
MPam0'5 |
cycles |
cycles |
cycles |
cycles |
2,05 |
4,30 |
- |
- |
- |
- |
1,85 |
4,07 |
7 139 |
7 527 |
14 355 |
13 409 |
1,65 |
3,83 |
15 518 |
16 395 |
31 119 |
29 712 |
1,45 |
3,58 |
25 527 |
27 031 |
51031 |
49 116 |
1,25 |
3,32 |
37 759 |
40 089 |
75 212 |
72 732 |
1,05 |
3,03 |
53 169 |
56 627 |
105 451 |
102 341 |
0,85 |
2,72 |
73 424 |
78 502 |
144 855 |
141 042 |
0,65 |
2,38 |
101 802 |
109 388 |
199471 |
194 885 |
0,45 |
1,98 |
146 015 |
158 005 |
283 365 |
278 004 |
0,25 |
1,47 |
231 455 |
253 422 |
444 329 |
438 619 |
0,05 |
0,66 |
5 561 901 |
5 604 650 |
19 522 952 |
19 515 242 |
b) Stress Gradient - Phase 1 | ||||||
Type of FCGR: |
WAA K^ 10MPa(m)0,5 const. |
AA6005A Kmax 10MPa(m)0'5 constant | ||||
Stress intensity ratio R: |
0,1 |
0,8 |
0,1 |
0,8 | ||
Crack |
Stress |
Fatigue |
Fatigue |
Fatigue |
Fatigue | |
length, |
itensity |
life, |
life |
life, |
life, | |
aj |
range, | |||||
mm |
MPam0,5 |
cycles |
cycles |
cycles |
cycles | |
2,05 |
6,82 |
- |
- |
- |
- | |
1,85 |
6,70 |
1 905 |
673 |
3 995 |
2 335 | |
1,65 |
6,61 |
3 877 |
1 395 |
8 124 |
4 760 | |
1,45 |
6,55 |
5 923 |
2 170 |
12 405 |
7 290 | |
1,25 |
6,48 |
8015 |
2 978 |
16 778 |
9 883 | |
1,05 |
6,36 |
10 188 |
3 847 |
21 316 |
12 591 | |
0,85 |
6,08 |
12 553 |
4 869 |
26 240 |
15 567 | |
0,65 |
5,71 |
15315 |
6 243 |
31 964 |
19 112 | |
0,45 |
5,14 |
18 765 |
8 350 |
39 063 |
23 666 | |
0,25 |
4,10 |
24 176 |
13 294 |
50 033 |
31 961 | |
0,05 |
1,99 |
42 254 |
32 843 |
85 148 |
66 467 |
Table B.7.5. Fatigue life predictions based on upperbound fatigue crack growth data for cast aluminium alloys from table B.3.4.
a) Uniform tension - Phase 1 | |||
Stress intensity ratio R: |
0,1 |
0,8 | |
Crack |
Stress |
Fatigue life, |
Fatigue life, |
length, |
intensity | ||
ai |
range, | ||
mm |
MPa(m)0'5 |
cycles |
cycles |
2,05 |
4,30 |
- |
- |
1,85 |
4,07 |
398 937 |
1 736 |
1,65 |
3,83 |
1 154 022 |
4 119 |
1,45 |
3,58 |
2 688 305 |
7 506 |
1,25 |
3,32 |
7 563 667 |
12 541 |
1,05 |
3,03 |
99 972 200 |
20 495 |
0,85 |
2,72 |
3,630109E+09 |
34 172 |
0,65 |
2,38 |
3,462941E+11 |
60 895 |
0,45 |
1,98 |
1,719760E+14 |
125 648 |
0,25 |
1,47 |
3,335859E+18 |
1 3278 202 |
0,05 |
0,66 |
1,680181E+30 |
6,315015E+12 |
b) Uniform tension - Phase 1 | |||
Stress intensity ratio R: |
0,1 |
0,8 | |
Crack |
Stress |
Fatigue life, |
Fatigue life, |
length, |
intensity | ||
ai |
range, | ||
mm |
MPa05 |
cycles |
cycles |
2,05 |
6,82 |
- |
- |
1,85 |
6,70 |
11 723 |
47 |
1,65 |
6,61 |
24 415 |
101 |
1,45 |
6,55 |
38 268 |
165 |
1,25 |
6,48 |
52 852 |
235 |
1,05 |
6,36 |
68 809 |
319 |
0,85 |
6,08 |
88 282 |
442 |
0,65 |
5,71 |
116 339 |
685 |
0,45 |
5,14 |
163 937 |
1 100 |
0,25 |
4,10 |
335 864 |
2 136 |
0,05 |
1,99 |
1,638740E+13 |
17 145 |
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