| |
Comparative Data on Heat-Resistant Alloys |
|
| Creep deformation is an important contributing factor to the distortion of many high temperature components. The cantilevered beam test provides visual demonstration of creep deformation. The alloys tested were allowed to deform under their own weight in a 2000°F (1095°C) furnace for 100 hours. The maximum bending stresses for the 0.125-inch (3 mm) sheet products were calculated to be 800 psi (5.5 MPa). Only the HR-120 alloy was capable of carrying its own weight! |
Comparative Stress-Rupture Strength |
|
Comparative Stress Rupture Strength |
| |
Approximate Stress Required
To Cause Rupture in 10,000 Hours |
| |
1400°F (760°C) |
1600°F (870°C) |
1800°F (980°C) |
Material |
Ksi |
MPa |
Ksi |
MPa |
Ksi |
MPa |
| HAYNES® HR-120® alloy |
12.0 |
83 |
5.8 |
40 |
1.9 |
13 |
| HASTELLOY® X alloy |
10.0 |
69 |
3.9 |
27 |
1.4 |
10 |
| RA 333® alloy |
9.2 |
63 |
3.1 |
21 |
1.05 |
7 |
| 800HT® alloy |
7.3 |
50 |
3.5 |
24 |
1.2 |
8 |
| Alloy 600 |
6.8 |
47 |
2.3 |
16 |
1.15 |
8 |
| 253 MA alloy |
5.2 |
36 |
2.5 |
17 |
1.15 |
8 |
| RA 85H alloy |
5.1 |
35 |
2.1 |
14 |
0.9 |
6 |
| Type 309 Stainless |
4.5 |
31 |
1.5 |
10 |
0.8 |
5 |
| INCOLOY® DS |
4.4 |
31 |
1.9 |
13 |
0.9 |
6 |
| RA 330 alloy |
4.3 |
30 |
1.7 |
12 |
0.63 |
4 |
| Type 310 Stainless |
4.0 |
28 |
1.5 |
10 |
1.0 |
7 |
| Type 446 Stainless |
1.1 |
8 |
0.45 |
3 |
0.23 |
2 |
|
Comparative 1% Creep Strength |
|
Approximate Stress Required
To Cause 1% Creep in 10,000 Hours |
|
1400°F (760°C) |
1600°F (870°C) |
1800°F (980°C) |
Material |
Ksi |
MPa |
Ksi |
MPa |
Ksi |
MPa |
| HAYNES HR-120 alloy |
10.0 |
69 |
5.1 |
35 |
1.1 |
8 |
| HASTELLOY X alloy |
7.5 |
52 |
3.1 |
21 |
1.0 |
7 |
| RA 333 alloy |
5.3 |
37 |
2.5 |
17 |
0.8 |
5 |
| 800HT alloy |
- |
- |
- |
- |
- |
- |
| Alloy 600 |
4.0 |
28 |
2.0 |
14 |
0.6 |
4 |
| 253 MA alloy |
4.2 |
29 |
1.8 |
12 |
0.5 |
3 |
| RA 85H alloy |
3.8 |
26 |
1.7 |
12 |
0.8 |
5 |
| Type 309 Stainless |
2.2 |
15 |
- |
- |
- |
- |
| INCOLOY DS alloy |
- |
- |
- |
- |
- |
- |
| RA 330 alloy |
3.6 |
25 |
1.9 |
13 |
0.17 |
1 |
| Type 310 Stainless |
2.9 |
15 |
- |
- |
- |
- |
| Type 446 Stainless |
- |
- |
- |
- |
- |
- |
|
Comparative Stress Rupture Life |
| The following are stress rupture life predictions, for selected combinations of temperature and stress, based upon standard log-log plot or Larson-Miller parameter extrapolations. All data are for solution-annealed plate or bar except where indicated. |
|
Estimated Stress Rupture Life (Hours) |
|
1400°F/15.0 Ksi |
1600°F/4.5 Ksi |
1800°F/2.0 Ksi |
Material |
(760°C/105 MPa) |
(870°C/ 31 MPa) |
(980°C/14 MPa) |
HAYNES® HR-120® alloy |
1700 |
38,500 |
10,000 |
HASTELLOY® X alloy |
900 |
5,000 |
2,100 |
RA 333 alloy |
300 |
1,500 |
800 |
800H alloy |
130 |
1,200 |
920 |
Alloy 600** |
15 |
280 |
580 |
253 MA alloy |
140 |
900 |
720 |
RA 85H alloy |
30 |
500 |
250 |
Alloy 601 |
50 |
1,200 |
1,000 |
Type 304 Stainless |
10 |
100 |
72 |
RA 330 alloy |
30 |
230 |
130 |
Type 310 Stainless* |
50 |
80 |
50 |
Type 446 Stainless |
<1 |
<1 |
<1
|
| * Sheet ** Mill Annealed |
| |
| Often the equipment operator is seeking to extend component life at elevated temperature. While comparing stress to cause rupture and stress to cause 1 percent creep for a given amount of hours can demonstrate a relative ranking for materials considered, an alternative perspective can be gained by examining the data presented in the above table. Comparative creep curves for various alloys are displayed below. The difference in life between stronger and weaker alloys when tested at the same temperature and stress can be as much as several orders of magnitude. This difference may sometimes be a consequence of seemingly small differences in the stress to produce failure or a finite level of creep in the same amount of hours, as shown in the previous tables on page 6. |
|
Average Tensile Data, Solution Heat-Treated (Plate)
|
|
Ultimate |
|
|
Test |
Tensile |
Yield Strength |
Elongation in |
Temperature |
Strength |
at 0.2% Offset |
2 in. (50.8 mm) |
°F |
(°C) |
Ksi |
MPa |
Ksi |
MPa |
% |
ROOM |
|
106.5 |
735 |
45.6 |
375 |
50 |
1000 |
(540) |
80.4 |
555 |
25.7 |
175 |
61 |
1200 |
(650) |
73.0 |
505 |
24.9 |
170 |
60 |
1400 |
(760) |
64.1 |
440 |
25.4 |
175 |
50 |
1600 |
(870) |
47.5 |
325 |
27.0 |
185 |
51 |
1800 |
(980) |
27.9 |
190 |
19.4 |
135 |
81 |
2000 |
(1095) |
15.1 |
105 |
9.1 |
63 |
89 |
2200 |
(1205) |
4.9 |
34 |
3.9 |
27 |
89 |
|
| Comparative Yield Strengths (Plate) |
|
