HAYNES® 214® alloy provides resistance
to oxidation at temperatures of 1750°F
(955°C) and above that is virtually
unmatched by any other wrought
heat-resistant alloy. It can be used for long-term continuous exposure
to combustion gases or air at
temperatures up to 2300°F (1260°C),
and, for shorter term exposures, it can
be used at even higher temperatures.Useful short-term oxidation resistance
has even been demonstrated at
temperatures as high as 2400°F
(1315°C).
|
Comparative Oxidation Resistance in Flowing Air* |
| |
Average Metal Affected in 1008 Hours** |
| |
1800°F (980°C) |
2000°F (1095°C) |
2100°F (1150°C) |
2200°F (1205°C) |
| Material |
Mils |
μm |
Mils |
μm |
Mils |
μm |
Mils |
μm |
|
| 214® alloy |
0.2 |
5 |
0.1 |
3 |
0.3 |
8 |
0.7 |
18 |
| 230® alloy |
0.7 |
18 |
1.3 |
33 |
3.4 |
86 |
7.9 |
201 |
| alloy 600 |
0.9 |
23 |
1.6 |
41 |
2.9 |
74 |
8.4 |
213 |
| alloy 601 |
1.3 |
33 |
2.6 |
66 |
5.3 |
135 |
7.5** |
191*** |
| RA330® alloy |
4.3 |
109 |
6.7 |
170 |
8.7 |
221 |
- |
- |
| alloy 800H |
1.8 |
46 |
7.4 |
188 |
8.9 |
226 |
13.6 |
289 |
| Type 446 SS |
2.3 |
58 |
14.5 |
368 |
>21.7 |
>551 |
>13.3 |
>592 |
| Type 316 SS |
14.3 |
363 |
>68.4 |
>1737 |
>105.0 |
>2267 |
>140.4 |
>3566 |
|
* Flowing air at a velocity of 7.0 feet/minute (213.4 cm/minute) past the samples. Samples cycled to room temperature once-a-week.
** Metal Loss + Average Internal Penetration.
*** 601 Sample exhibited very large internal voids. |
|
Metallographic Technique used for Evaluating Environmental Tests |
 |
Comparative Oxidation in Flowing Air 2100°F (1150°C) |
| Microstructures shown are for
coupons exposed for 1008
hours at 2100°F (1150°C) in
air flowing at 7.0 feet/minute
(213.4 cm/minute) past the
samples. Samples were
descaled by cathodically
charging the coupons while
they were immersed in a
molten salt solution. The black
area shown at the top of each
picture represents actual metal
loss due to oxidation. The
data clearly show HAYNES®
214® alloy is only slightly
affected by the exposure,
while other nickel-chromium
alloys, such as alloys 600 and
601, and ironnickel chromium
alloys, such as RA330® alloy,
all exhibit significantly more
oxidation damage. Of particular
importance is the almost total
absence of internal attack for
the 214 alloy. This contrasts
markedly with the very
substantial amount of internal
attack evidenced by the alloy
601 and RA330 alloy tests
coupons. The nature of this
internal attack, as illustrated
by the photomicrographs, is
common for alloys containing
1-2% aluminum or silicon. Such
levels of these elements do
promote chromium oxide scale
adherence, but do not afford
improved resistance to oxide
penetration below the scale. |
|
HAYNES® 214® alloy
Average Metal Affected
= 0.3 Mils (8 μm) |
|
Alloy 600
Average Metal Affected
= 2.9 Mils (74 μm) |
|
Alloy 600
Average Metal Affected
= 5.3 Mils (135 μm) |
|
RA330 alloy
Average Metal Affected
= 8.7 Mils (221 μm) |
|
Comparative Burner Rig Oxidation Resistance |
| |
Average Metal Affected in 1008 Hours** |
| |
Metal Loss Average |
Metal Affected* |
Metal Loss Average |
Metal Affected* |
| Material |
Mils |
μm |
Mils |
μm |
Mils |
μm |
Mils |
μm |
|
| 214® alloy |
0.4 |
10 |
1.0 |
25 |
0.5 |
13 |
1.2 |
30 |
| 230® alloy |
0.8 |
20 |
2.8 |
71 |
2.2 |
56 |
5.2 |
132 |
| HASTELLOY® X alloy |
2.7 |
69 |
5.6 |
142 |
9.0 |
229 |
12.9 |
328 |
| RA330® alloy |
7.8 |
198 |
11.8 |
300 |
10.9 |
277 |
12.9 |
328 |
| alloy 600 |
12.3a |
312a |
14.4a |
366a |
17.2 |
437 |
19.5 |
495 |
| alloy 800H |
12.3 |
312 |
14.5 |
368 |
30.5b |
775b |
33.4b |
848b |
| Type 310 Stainless |
13.7 |
348 |
16.2 |
411 |
21.2 |
538 |
23.7 |
602 |
| alloy 601 |
3.0 |
76 |
18.8 |
478 |
10.7 |
272 |
>24.0c |
>610c |
|
* Metal Loss + Average Internal Penetration.
a Extrapolated from 917 hours
b Extrapolated from 400 hours
c Internal penetration through entire thickness |
|
Oxidation Test Parameters
Burner rig oxidation tests were
conducted by exposing, in a rotating
holder, samples 0.375 inch x 2.5
inches x thickness (9.5mm x 64mm x thickness) to the products of
combustion of fuel oil (2 parts No. 1
and 1 part No. 2) burned at a ratio of
air to fuel of about 50:1. (Gas velocity
was about 0.3 mach). Samples were automatically removed from the gas
stream every 30 minutes and fan
cooled to less than 500°F (260°C) and
then reinserted into the flame tunnel. |
Comparative Burner Rig Oxidation Resistance at 1800°F (980°C) / 1000 Hours |
 |
Comparative Burner Rig Oxidation Resistance at 2000°F (1095°C) / 500 Hours |
 |