Type
Analysis
|
Element
|
Min
|
Max
|
|
Molybdenum
|
15.0
|
17.0
|
|
Chromium
|
14.5
|
16.5
|
|
Iron
|
4.00
|
7.00
|
|
Tungsten
|
3.00
|
4.50
|
|
Cobalt
|
--
|
2.50
|
|
Carbon
|
--
|
0.02
|
|
Silicon
|
--
|
0.08
|
|
Manganese
|
--
|
1.00
|
|
Vanadium
|
--
|
0.35
|
|
Phosphorus
|
--
|
0.03
|
|
Sulfur
|
--
|
0.03
|
|
Nickel
|
Remainder
|
Description
Hastelloy C-276 is a
nickel-molybdenum-chromium-tungsten alloy with excellent general
corrosion resistance and good fabricability. The alloy should be
considered for use in environments where resistance to hot
contaminated mineral acids, organic and inorganic
chloride-contaminated media, chlorine, formic and acetic acids,
acetic , acetic anhydride, sea water and brine solutions is
desired.
Hastelloy C-276 has resisted the formation of grain
boundary precipitates in the weld heat-affected zone, making it a
candidate for most chemical and petrochemical processing applications
in the as-welded condition. The alloy has resisted both general and
localized corrosion, including pitting, crevice corrosion, and stress
corrosion cracking.
Hastelloy C-276 is readily fabricated by
welding, using methods similar to those utilized for nickel-based
alloys.
Corrosion
Resistance
Hastelloy C-276 is balanced to
provide excellent corrosion resistance to a variety of chemical
process environments. This alloy has provided resistance to hot
contaminated mineral acids, organic and inorganic chloride
contaminated media, hypochlorite, chlorine dioxide solutions, formic
and acetc acids, acetic anhydride, sea water and brine solutions.
Typical General Corrosion Rates*
|
Environment
|
Concentration
(%
by weight)
|
Test
Temperature
|
Penetration
Rate (per year)
|
|
°F
|
°C
|
Unwelded**
|
As-welded***
|
Welded
and
heat-treated**
|
|
mils
|
mm
|
mils
|
mm
|
mils
|
mm
|
|
Formic
Acid
Hydrochloric Acid
Hydrochloric Acid
Hydrochloric
Acid
Hydrochloric Acid
Sulfuric Acid
Sulfuric Acid
|
20
10
10
10+0.5
NaOCl
3.5+8 Fe Cl3
10
85
|
Boiling
150
167
167
190
Boiling
167
|
Boiling
66
75
75
88
Boiling
75
|
4.8
21.
40.
46.
--
15.
17.
|
0.12
0.53
1.02
1.17
--
0.38
0.43
|
3.5
20.
50.
50.
5.
14.
17.
|
0.09
0.51
1.27
1.27
0.13
0.36
0.43
|
3.60
21.
--
--
--
18.
--
|
0.09
0.53
--
--
--
0.46
--
|
*Determined in
laboratory tests. It is recommended that samples be tested under
actual plant conditions.
**Solution heat-treated
***Gas
tungsten-arc welded.
Workability
Hastelloy C-276 can be forged,
hot-upset, and impact extruded. Although the alloy tends to
work-harden, it can be successfully deep-drawn, spun, press formed or
punched. All of the common methods of welding can be used to weld
alloy C-276, although the oxy-acetylene and submerged arc processes
are not recommended when the fabricated item is intended for use in
corrosion service. Special precautions should be taken to avoid
excessive heat in-put.
Welding
Gas tungsten-arc
welding, gas metal-arc welding, shielded metal-arc (coated electrode)
welding, or resistance welding may be used. Minimum heat input
consistent with adequate penetration reduces the chance of
hot-cracking. Oxyacetylene welding should be avoided due to
possibility of carburization. Hastelloy C-276 can be used in the
as-welded condition in most chemical and petrochemical process
equipment.
Heat-Treatment
Wrought forms of Hastelloy C-276 are
furnished in the solution heat-treated condition unless otherwise
specified. Alloy C-276 is normally solution heat-treated at 2050 °F
and rapid quenched. Parts which have been hot-formed should be
solution heat-treated prior to final fabrication or installation, if
possible.
Average
Physical Properties
|
Physical
Properties
|
°F
|
British
Units
|
°C
|
Metric
Units
|
|
Density
|
72
|
0.321 lb./in.(3)
|
22
|
8.89 g/cm(3)
|
|
Melting Range
|
2415-
2500
|
|
1323-
1371
|
|
|
Electrical
Resistivity
|
75
|
51 microhm-in.
|
24
|
1.30 microhm-m
|
|
Mean
Coefficient
of Thermal
Expansion
|
75-200
|
6.2 microin./in.-°F
|
24-93
|
11.2 X 10(-6)m/m-K
|
|
75-400
|
6.7 microin./in.-°F
|
24-204
|
12.0 X 10(-6)m/m-K
|
|
75-600
|
7.1 microin./in.-°F
|
24-316
|
12.8 X 10(-6)m/m-K
|
|
75-800
|
7.3 microin./in.-°F
|
24-427
|
13.2 X 10(-6)m/m-K
|
|
75-1000
|
7.4 microin./in.-°F
|
24-538
|
13.4 X 10(-6)m/m-K
|
|
75-1200
|
7.8 microin./in.-°F
|
24-649
|
14.1 X 10(-6)m/m-K
|
|
75-1400
|
8.3 microin./in.-°F
|
24-760
|
14.9 X 10(-6)m/m-K
|
|
75-1600
|
8.8 microin./in.-°F
|
24-871
|
15.9 X 10(-6)m/m-K
|
|
75-1700
|
8.9 microin./in.-°F
|
24-927
|
16.0 X 10(-6)m/m-K
|
|
Thermal
Conductivity
|
-270
|
50 Btu-in/ft²-hr-°F
|
-168
|
7.2 W/m-K
|
|
-100
|
60 Btu-in/ft²-hr-°F
|
-73
|
8.6 W/m-K
|
|
0
|
65 Btu-in/ft²-hr-°F
|
32
|
9.4 W/m-K
|
|
100
|
71 Btu-in/ft²-hr-°F
|
38
|
10.2 W/m-K
|
|
200
|
77 Btu-in/ft²-hr-°F
|
93
|
11.1 W/m-K
|
|
400
|
90 Btu-in/ft²-hr-°F
|
204
|
13.0 W/m-K
|
|
600
|
104 Btu-in/ft²-hr-°F
|
316
|
15.0 W/m-K
|
|
800
|
117 Btu-in/ft²-hr-°F
|
427
|
16.9 W/m-K
|
|
1000
|
132 Btu-in/ft²-hr-°F
|
538
|
19.0 W/m-K
|
|
1200
|
145 Btu-in/ft²-hr-°F
|
649
|
20.9 W/m-K
|
|
1400
|
159 Btu-in/ft²-hr-°F
|
760
|
22.9 W/m-K
|
|
1600
|
173 Btu-in/ft²-hr-°F
|
871
|
24.9 W/m-K
|
|
1800
|
185 Btu-in/ft²-hr-°F
|
982
|
26.7 W/m-K
|
|
2000
|
195 Btu-in/ft²-hr-°F
|
1093
|
28.1 W/m-K
|
Average Dynamic Modulus of
Elasticity
|
Form
|
Condition
|
Test
Temp,
°F(°C)
|
Average
Dynamic Modulus of
Elasticity,10(6) psi (GPa)
|
|
Plate
|
Heat-treated
at
2050 °F
(1121 °C),
Rapid Quenched
|
Room
|
29.8 (205)
|
|
400 (204)
|
28.3 (195)
|
|
600 (316)
|
27.3 (188)
|
|
800 (427)
|
26.4 (182)
|
|
1000 (538)
|
25.5 (176)
|
Average Room Temperature Hardness
|
Form
|
Hardness,
Rockwell
|
|
Sheet
|
Rb 90
|
|
Plate
|
Rb 87
|
Average Tensile Data
|
Form
|
Condition
|
Test
Temp.,
°F(°C)
|
Ultimate
Tensile
Strength
ksi
(MPa)
|
Yield
Strength
at
0.2% offset
ksi (MPa)
|
Elongation
in
2" percent
|
|
Sheet, 0.063 to
0.187" Thick
|
Heat treated at
2050
°F
Rapid Quenched
|
400 (204)
600
(316)
800 (427)
1000 (538)
|
100.8 (695)
97.0
(669)
95.0 (655)
88.9 (613)
|
42.1 (290)
37.7
(260)
34.8 (240)
33.8 (233)
|
56
64
65
60
|
|
Plate, 3/16
to
1.000" Thick
|
Heat treated at
2050
°F
Rapid Quenched
|
400 (204)
600
(316)
800 (427)
1000 (538)
|
98.9 (682)
94.3
(650)
91.5 (631)
87.2 (601)
|
38.2 (263)
34.1
(235)
32.7 (235)
32.8 (226)
|
61
66
60
59
|
|
Plate, 1.000"
Thick
|
Heat treated at
2050
°F
Rapid Quenched
|
Room
600
(316)
800 (427)
|
113.9 (785)
96.3
(664)
94.8 (654)
|
52.9 (365)
36.2
(250)
30.5 (210)
|
59
63
61
|
Average Oxidation Data
|
Test
Temperature,
°F(°C)
|
Average
Oxidation Rate per 100-hour test period
|
|
100
hours,continuous
mils mm
|
100
hours,intermittent
mils mm
|
|
1800 (982)
|
0.11
|
0.003
|
0.11
|
0.003
|
|
1900 (1038)
|
0.22
|
0.006
|
0.18
|
0.005
|
|
2000 (1093)
|
1.62
|
0.041
|
2.88
|
0.073
|
|
