Part One Fatigue Data
1. Q235B
Comparison before and after UIT on butt-joint seam |
No. |
State |
Fatigue life
N×10-6/r |
Fracture Location |
Stess σ/MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture Location |
Stress
σ/MPa |
1 |
As welded |
2.752 |
Toe zone |
160 |
11 |
UIT |
1.199 |
Toe zone |
265 |
2 |
As welded |
1.885 |
Toe zone |
170 |
12 |
UIT |
0.816 |
Toe zone |
270 |
3 |
As welded |
1.645 |
Toe zone |
175 |
13 |
UIT |
0.448 |
Base metal |
270 |
4 |
As welded |
1.415 |
Toe zone |
180 |
14 |
UIT |
0.483 |
Toe zone |
280 |
5 |
As welded |
0.721 |
Toe zone |
190 |
15 |
UIT |
0.278 |
Toe zone |
290 |
6 |
As welded |
0.546 |
Toe zone |
210 |
16 |
UIT |
1.836 |
Base metal |
265 |
7 |
As welded |
0.328 |
Toe zone |
230 |
17 |
UIT |
0.888 |
Base metal |
270 |
8 |
UIT |
3.996 |
Toe zone |
250 |
18 |
UIT |
0.848 |
Base metal |
270 |
9 |
UIT |
3.210 |
Base metal |
255 |
19 |
UIT |
0.533 |
Base metal |
270 |
10 |
UIT |
1.848 |
Toe zone |
260 |
20 |
UIT |
0.443 |
Base metal |
270 |
Comparison before and after UIT on cruciform-joint seam |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture Location |
Stress σ/MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture Location |
Stress
σ/MPa |
1 |
As welded |
2.605 |
Toe zone |
183 |
11 |
UIT |
1.538 |
Toe zone |
319 |
2 |
As welded |
1.875 |
Toe zone |
198 |
12 |
UIT |
1.28 |
Toe zone |
334 |
3 |
As welded |
0.874 |
Toe zone |
214 |
13 |
UIT |
0.611 |
Base Metal |
334 |
4 |
As welded |
0.532 |
Toe zone |
244 |
14 |
UIT |
0.645 |
Toe zone |
349 |
5 |
As welded |
0.301 |
Toe zone |
274 |
15 |
UIT |
0.387 |
Toe zone |
364 |
6 |
UIT |
3.320 |
Toe zone |
304 |
|
|
|
|
|
Comparison of fatigue life before and after UIT |
Joint style |
State |
Stressσ/MPa |
Fatigue life N×10-6/r |
Butt joint |
As welded |
253 |
0.165 |
Butt joint |
UIT |
253 |
10.0 |
Cruciform joint |
As welded |
281 |
0.24 |
Cruciform joint |
UIT |
281 |
10 |
Comparison of fatigue strength before and after UIT |
Joint style |
Fatigue strength(σ/MPa) |
Increase(/%) |
As welded |
UIT |
Butt joint |
149 |
235 |
57 |
Cruciform joint |
143 |
234 |
64 |
Cruciform joint(R=0.5) |
168 |
288 |
71 |
2. 16Mn
Comparison of butt-joint seam before and after UIT |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress σ/MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
σ/MPa |
1 |
As welded |
2.969 |
Toe zone |
165 |
7 |
UIT |
1.570 |
Toe zone |
320 |
2 |
As welded |
1.633 |
Toe zone |
172 |
8 |
UIT |
1.220 |
Base metal |
330 |
3 |
As welded |
0.846 |
Toe zone |
190 |
9 |
UIT |
0.450 |
Toe zone |
340 |
4 |
As welded |
0.607 |
Toe zone |
210 |
10 |
UIT |
0.174 |
Toe zone |
350 |
5 |
As welded |
0.402 |
Toe zone |
230 |
11 |
UIT |
0.114 |
Toe zone |
360 |
6 |
UIT |
2.401 |
Base metal |
310 |
|
|
|
|
|
Comparison of cruciform-joint before and after UIT |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stressσ/MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
σ/MPa |
1 |
As welded |
3.640 |
Toe zone |
140 |
6 |
UIT |
0.137 |
Toe zone |
290 |
2 |
As welded |
2.607 |
Toe zone |
145 |
7 |
UIT |
0.420 |
Toe zone |
270 |
3 |
As welded |
1.537 |
Toe zone |
150 |
8 |
UIT |
0.872 |
Toe zone |
260 |
4 |
As welded |
0.816 |
Toe zone |
170 |
9 |
UIT |
1.546 |
Toe zone |
250 |
5 |
As welded |
0.393 |
Toe zone |
210 |
10 |
UIT |
2.454 |
Toe zone |
240 |
Comparison of fatigue life before and after UIT |
Joint style |
State |
Stress
σ/MPa |
Fatigue life
N×10-6/r |
Butt-joint |
As welded |
281 |
0.104 |
Butt-joint |
UIT |
281 |
10.0 |
Cruciform-joint |
As welded |
207 |
0.298 |
Cruciform-joint |
UIT |
207 |
10.0 |
Stress concentration factor |
Joint style |
State |
Knuckle radius |
Efficient stress concentration factor |
ρ/mm |
Butt-joint |
As welded |
0.2 |
0.104 |
Butt-joint |
UIT |
1.6 |
10.0 |
Cruciform-joint |
As welded |
0.4 |
0.298 |
Cruciform-joint |
UIT |
2.0 |
10.0 |
Comparison of Fatigue strength before and after UIT |
Joint style |
Fatigue strength(/MPa) |
Increase(/%) |
As welded |
UIT |
Butt-joint |
150.5 |
286 |
90 |
Cruciform-joint |
132 |
220.5 |
67 |
3. Varying-amplitude load
a) Q235
Comparison of fatigue life |
State |
Constant-amplitude |
Varying-amplitude |
As welded |
UIT |
As welded |
UIT |
Stress(σ/MPa) |
189 |
189 |
182 |
182 |
Fatigue life(N×10-6/r) |
0.20 |
4.40 |
0.4 |
2.27 |
Stress(σ/MPa) |
177.0 |
177.0 |
163.5 |
163.5 |
Fatigue life(N×10-6/r) |
0.275 |
10.000 |
0.560 |
10.000 |
Comparison of fatigue strength(2×106) |
State |
Constant-amplitude |
Varying-amplitude |
As welded |
UIT |
As welded |
UIT |
Fatigue strength(σ/MPa) |
117 |
200 |
109 |
184 |
Increase(/%) |
- |
71 |
- |
69 |
b) 16Mn
Comparison of fatigue life |
State |
Constant-amplitude |
Varying-amplitude |
As welded |
UIT |
TIG dressing |
As welded |
UIT |
TIG dressing |
Stress(σ/MPa) |
|
227 |
|
|
203 |
|
Fatigue life(N×10-6/r) |
0.20 |
0.47 |
0.50 |
0.40 |
1.39 |
.075 |
Stress(σ/MPa) |
|
189 |
|
|
178 |
|
Fatigue life(N×10-6/r) |
0.372 |
10.0 |
0.925 |
0.57 |
10.0 |
1.13 |
Comparison of fatigue strength(2×106) |
State |
Constant-amplitude |
Varying-amplitude |
As welded |
UIT |
TIG dressing |
As welded |
UIT |
TIG dressing |
Fatigue strength(σ/MPa) |
115 |
212 |
158 |
110 |
198 |
147 |
Increase(/%) |
- |
84 |
37 |
- |
80 |
34 |
4. LF21
Comparison of Cruciform-joint(R=0.5) |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
MPa |
1 |
As welded |
3.474 |
Toe zone |
29 |
6 |
UIT |
0.483 |
Toe zone |
56 |
2 |
As welded |
2.466 |
Toe zone |
34 |
7 |
UIT |
0.743 |
Base metal |
52 |
3 |
As welded |
1.300 |
Toe zone |
38 |
8 |
UIT |
0.816 |
Toe zone |
50 |
4 |
As welded |
0.383 |
Toe zone |
47 |
9 |
UIT |
1.654 |
Toe zone |
44 |
5 |
As welded |
0.345 |
Toe zone |
54 |
10 |
UIT |
2.896 |
Toe zone |
40 |
Comparison of T joint(R=0.1) |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
MPa |
1 |
As welded |
0.60 |
Toe zone |
84 |
7 |
UIT |
0.275 |
Toe zone |
112 |
2 |
As welded |
0.273 |
Toe zone |
122 |
8 |
UIT |
0.679 |
Toe zone |
105 |
3 |
As welded |
1.80 |
Toe zone |
72 |
9 |
UIT |
1.047 |
Toe zone |
100 |
4 |
As welded |
4.15 |
Toe zone |
63 |
10 |
UIT |
1.453 |
Toe zone |
97 |
5 |
As welded |
0.910 |
Toe zone |
84
|
11 |
UIT |
2.745 |
Toe zone |
93 |
6 |
As welded |
1.37 |
Toe zone |
76 |
|
|
|
|
|
Comparison of T joint(R=-1) |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
MPa |
1 |
As welded |
1.069 |
Toe zone |
72 |
7 |
UIT |
0.426 |
Toe zone |
116 |
2 |
As welded |
3.45 |
Toe zone |
68 |
8 |
UIT |
1.589 |
Toe zone |
100 |
3 |
As welded |
0.3 |
Toe zone |
100 |
9 |
UIT |
0.662 |
Toe zone |
107 |
4 |
As welded |
0.74 |
Toe zone |
84 |
10 |
UIT |
5.389 |
Toe zone |
95 |
5 |
As welded |
0.5 |
Toe zone |
92 |
11 |
UIT |
0.603 |
Toe zone |
112 |
6 |
As welded |
0.79 |
Toe zone |
77 |
|
|
|
|
|
Comparison of fatigue strength |
Joint style |
State |
应力比 |
Fatigue strength(/MPa) |
Increase(/%) |
T joint |
UIT |
R=-1 |
101 |
44 |
|
As welded |
R=-1 |
70 |
T joint |
UIT |
R=0.1 |
96 |
37 |
|
As welded |
R=0.1 |
70 |
Cruciform-joint |
UIT |
R=0.5 |
42 |
26 |
|
As welded |
R=0.5 |
34 |
5. SS800 high-tensile steel
Comparison of different methods |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stressσ/MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
σ/MPa |
1 |
TIG dressing |
0.398 |
Dressing Toe zone |
266 |
7 |
UIT |
3.182 |
Toe zone |
285 |
2 |
TIG dressing |
0.347 |
Dressing Toe zone |
247 |
8 |
UIT |
1.907 |
Base metal |
295 |
3 |
TIG dressing |
1.024 |
Toe zone |
228 |
9 |
UIT |
1.062 |
Toe zone |
304 |
4 |
TIG dressing |
1.287 |
Dressing Toe zone |
219 |
10 |
UIT |
0.584 |
Toe zone |
314 |
5 |
TIG dressing |
0.687 |
Toe zone |
205 |
11 |
UIT |
0.160 |
Toe zone |
352 |
6 |
TIG dressing |
2.018 |
Dressing Toe zone |
200 |
|
|
|
|
|
Comparison of Fatigue life |
State |
Stress
σ/MPa |
Fatigue life
N×10-5/r |
Stress
σ/MPa |
Fatigue life
N×10-5/r |
As welded |
340 |
0.5 |
261 |
1.59 |
UIT |
340 |
2.3 |
261 |
100 |
TIG dressing |
340 |
0.68 |
261 |
3.7 |
TIG dressing+ UIT |
340 |
14.5 |
261 |
200 |
Increase of fatigue strength(2×106) |
State |
As welded |
TIG dressing |
UIT |
TIG dressing +UIT |
Fatigue strength(σ/MPa) |
150 |
163 |
282 |
315 |
Increase(/%) |
- |
68 |
190 |
225 |
Increase of fatigue strength(2×106) |
Joint style |
Fatigue strength(σ/MPa) |
Increase(/%) |
As welded |
UIT |
Double welded butt-joint |
150 |
293 |
95 |
single welded butt-joint |
132 |
307 |
132 |
Endwise corner joint |
98 |
267 |
173 |
Comparison of fatigue life |
Joint style |
State |
Stress
σ/MPa |
Fatigue life
N×10-5/r |
Stress
σ/MPa |
Fatigue life
N×10-5/r |
Single welded Butt-joint |
As welded |
268 |
1.0 |
286 |
0.75 |
|
UIT |
268 |
49 |
286 |
100 |
Double welded Butt-joint |
As welded |
290 |
1.0 |
261 |
1.59 |
|
UIT |
290 |
22.5 |
261 |
100 |
Endwise corner joint |
As welded |
255 |
1.0 |
229 |
1.4 |
|
UIT |
255 |
33 |
229 |
100 |
6. BT20 Titanium alloy
Comparison of fatigue life |
State |
Stressσ/MPa |
Fatigue life N×10-5/r |
Stress σ/MPa |
Fatigue lifeN×10-5/r |
As welded |
256 |
1.0 |
235 |
2.5 |
UIT |
256 |
29 |
235 |
100 |
As welded |
323 |
1.0 |
224 |
10.7 |
UIT |
323 |
3.05 |
224 |
100 |
Comparison of fatigue strength (2×106) |
State |
TIG |
Electron beam welding |
As welded |
UIT |
As welded |
UIT |
Fatigue strength(σ/MPa) |
204 |
260 |
192 |
265 |
Increase(/%) |
- |
27 |
- |
38 |
7. X65 pipe steel
Comparison of fatigue life |
State |
Stressσ/MPa |
Fatigue life N×10-5/r |
Stressσ/MPa |
Fatigue life N×10-5/r |
As welded |
381 |
1.0 |
254 |
9.3 |
UIT |
381 |
1.85 |
254 |
100 |
8. 20# steel T-joint
Comparison of fatigue life |
Attribute Style |
State |
Stressσ/MPa |
Fatigue life
N×10-5/r |
Stress
σ/MPa |
Fatigue life
N×10-6/r |
热点应力 |
As welded |
446 |
1.0 |
172 |
1.65 |
UIT |
446 |
4.8 |
172 |
10 |
名义应力 |
As welded |
131 |
1.0 |
49 |
2.0 |
UIT |
131 |
4.7 |
49 |
10 |
9. After UIT
UIT results (R=0.1) |
No. |
Group |
Fatigue life
N×10-6/周 |
Fracture location |
Stressσ/MPa |
No. |
Group |
Fatigue life
N×10-6/周 |
Fracture location |
Stress
σ/MPa |
1 |
Heat procession |
0.123 |
Toe zone |
245 |
7 |
Without heat procession |
3.464 |
Base metal |
189 |
2 |
Heat procession |
0.362 |
Toe zone |
230 |
8 |
Without heat procession |
1.897 |
Base metal |
198 |
3 |
Heat procession |
0.624 |
Toe zone |
217 |
9 |
Without heat procession |
1.358 |
Base metal |
207 |
4 |
Heat procession |
1.472 |
Toe zone |
205 |
10 |
Without heat procession |
1.105 |
Toe zone |
216 |
5 |
Heat procession |
3.282 |
Toe zone |
195 |
11 |
Without heat procession |
0.585 |
Toe zone |
225 |
6 |
Without heat procession |
10.17 |
Not break |
180 |
|
|
|
|
|
UIT results(R=-1) |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stressσ/MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
σ/MPa |
1 |
Heat procession |
1.676 |
Base metal |
295 |
7 |
Without heat procession |
2.014 |
Base metal |
280 |
2 |
Heat procession |
1.185 |
Base metal |
303 |
8 |
Without heat procession |
1.430 |
Base metal |
300 |
3 |
Heat procession |
0.867 |
Base metal |
315 |
9 |
Without heat procession |
1.045 |
Toe zone |
300 |
4 |
Heat procession |
0.456 |
Toe zone |
330 |
10 |
Without heat procession |
0.647 |
Toe zone |
320 |
5 |
Heat procession |
0.429 |
Toe zone |
350 |
11 |
Without heat procession |
0.498 |
Toe zone |
340 |
6 |
Without heat procession |
2.997 |
Base metal |
270 |
|
|
|
|
|
UIT results(R=0.45) |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stressσ/MPa |
No. |
Group |
Fatigue life
N×10-6/r |
Fracture location |
Stress
σ/MPa |
1 |
Heat procession |
0.253 |
Toe zone |
188 |
6 |
Without heat procession |
0.371 |
Toe zone |
188 |
2 |
Heat procession |
0.411 |
Toe zone |
180 |
7 |
Without heat procession |
0.507 |
Toe zone |
179 |
3 |
Heat procession |
0.641 |
Toe zone |
171 |
8 |
Without heat procession |
1.001 |
Toe zone |
170 |
4 |
Heat procession |
1.189 |
Toe zone |
165 |
9 |
Without heat procession |
1.434 |
Toe zone |
161 |
5 |
Heat procession |
2.299 |
Toe zone |
157 |
10 |
Without heat procession |
3.989 |
Toe zone |
152 |
|