Home / HASTELLOY® C-22HS® alloy

Principal FeaturesNominal CompositionTensile Properties of Cold-worked MaterialImpact StrengthFracture ToughnessHardnessCompressive StrengthResistance to Sour Gas EnvironmentsResistance to Hydrogen EmbrittlementResistance to AcidsDynamic ModulusHigh-Cycle FatigueHardness ProfileThermal StabilityResistance of Welds to Sour Gas EnvironmentsWeld Mechanical PropertiesSpecificationsDisclaimerAlloy Brochure

Principal Features

A high strength C-type alloy for the Oil and Gas Industries

HASTELLOY® C-22HS® alloy (N07022) is the premier nickel-chromium-molybdenum, corrosion-resistant material for oil and gas industry use. Cold working of the alloy at levels between 30 and 65% result in high room temperature yield strengths. It exhibits exceptional resistance to sour gas environments and is NACE/ISO approved.

Product Forms

C-22HS® alloy is available in the form of plate, sheet, strip, billet, bar, wire, pipe, and tube. Round products in the form of solid bars are available up to 10″ with various amounts of cold work to achieve high strength and toughness by simultaneously retaining the excellent corrosion resistance of the alloy.

Oil & Gas Applications

The data in this document is believed to be useful for applications in the oil & gas industry, or other industries which may require an alloy with excellent corrosion resistance and strength levels higher than “standard” HASTELLOY® C-22® alloy. For additional oil and gas information on C-22HS®, please click here.

Available in Three Very High-Strength Conditions

Early testing of C-22HS® alloy was focused on material in the annealed + age-hardened condition where the material was annealed at 1975°F (1079°C) and age-hardened at 1300°F (704°C)/16h/Furnace cool (FC) to 1125°F (607°C)/32h/Air-cool (AC.) In this “standard condition” C-22HS® alloy will typically have strengths around 100 ksi (690 MPa). While this strength level is almost double of “C-type” alloys in the annealed condition, many oil and gas applications require even greater strength. For this reason, a considerable development effort has been generated on C-22HS® alloy in three other “very high strength” conditions:

1) Cold Worked

2) Cold Worked + Age-HardenedA

3) Low Temperature (LT) AnnealedB + Age-HardenedC

A1125°F (607°C)/10h/AC B1850°F (1010°C) C1300°F (704°C)/16h/FC to 1125°F (607°C)/32h/AC

A comparison of yield strengths for the three very high strength conditions is shown below along with that of the annealed and “standard” conditions. Haynes does not recommend use of highly cold worked and aged material because the increase in yield strengths is minimal and the susceptibility to hydrogen embrittlement in severe oil well conditions is increased.

*Please contact our technical support team if you have technical questions about this alloy.

Nominal Composition

Weight %
Nickel 61 Balance
Cobalt 1 max.
Chromium 21
Molybdenum 17
Iron 2 max.
Tungsten 1 max.
Manganese 0.8 max.
Aluminum 0.5 max.
Silicon 0.08 max.
Carbon 0.01 max.
Copper 0.5 max.

Tensile Properties of Cold-worked Material

Average Room Temperature Tensile Properties of Bar
(Cold-worked in the Range 43-47%)

Condition 0.2% OffsetYield Strength Ultimate TensileStrength Elongation Reduction of Area
ksi MPa ksi MPa % %
Cold-worked Bar 198.0 1365 203.5 1403 16.7 64.2

Room Temperature Tensile Properties of Bar as a Function of Diameter and Percentage Cold-work

Bar Diameter* Cold-work Room Temperature Tensile Properties
0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
in mm % ksi MPa ksi MPa %
0.5 12.7 43 191.1 1317 196.5 1355 18.2
0.75 19.1 44 204.7 1411 210.0 1448 15.5
1.0 25.4 44 188.3 1298 193.8 1336 17.6
1.25 31.8 46 205.2 1415 210.9 1454 15.4
1.567 39.8 37 184.2 1270 192.7 1329 17.4
2.0 50.8 47 207.5 1431 212.0 1462 13.0
2.375 60.3 54 181.4 1251 190.5 1313 21.2
2.5 63.5 49 180.0 1241 183.7 1267 18.2
3.62 91.9 42 192.3 1326 197.3 1360 14.0

*Averages from duplicate test samples

Room and Elevated Temperature Tensile Properties of 0.5 in Diameter
Cold-worked (43%) Bar

Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation Reduction of Area
°F °C ksi MPa ksi MPa % %
RT RT 195.1 1345 200.4 1382 18.0 65.2
400 204 181.8 1254 182.6 1259 14.6 63.1
500 260 181.0 1248 181.1 1249 14.1 60.8

Room and Elevated Temperature Tensile Properties of 2.375 in Diameter Cold-worked (54%) Bar as a Function of Orientation (Longitudinal and Transverse)

Test Temperature Orientation 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation Reduction of Area
°F °C  - ksi MPa ksi MPa % %
RT RT Longitudinal 181.4 1251 190.5 1313 21.2 71.1
Transverse 156.6 1080 183.0 1262 18.8 60.9
350 177 Longitudinal 160.2 1105 166.6 1149 18.5 72.2
Transverse 138.3 954 160.9 1109 16.1 59.6
450 232 Longitudinal 156.1 1076 163.1 1125 18.3 72.2
Transverse 139.0 958 156.7 1080 14.8 59.3

Average Room Temperature Tensile Properties of Tube
(Cold-worked in the Range 52-53%)

Condition 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
ksi MPa ksi MPa %
Cold-worked Tube 187.3 1291 195.0 1345 15.1

Room and Elevated Temperature Tensile Properties of Cold-worked Tube
(3.5 in Diameter by 0.43 in Wall Thickness) (52-53%) as a Function of Orientation
(Longitudinal and Transverse)

Test TemperatureOrientation0.2% Offset Yield StrengthUltimate Tensile StrengthElongationReduction of Area

Test Temperature Orientation 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation Reduction of Area
°F °C ksi MPa ksi MPa % %
RT RT Longitudinal 166.0 1145 180.4 1244 18.8 69.5
Transverse 156.3 1078 175.8 1212 29.2 63.6
400 204 Longitudinal 149.3 1029 157.6 1087 16.8 68.7
Transverse 143.2 987 155.1 1069 25.8 64.8
500 260 Longitudinal 147.6 1018 154.2 1063 16.5 67.1
Transverse 138.0 951 151.4 1044 24.8 60.9
600 316 Longitudinal 144.9 999 151.5 1045 16.9 66.4
Transverse 135.7 936 147.5 1017 25.5 62.3

Values are averages from 10 tests
RT= Room Temperature

Statistical Temperature De-rating C-22HS® Cold-worked Tubing

Impact Strength

C-22HS® Alloy Room Temperature Charpy V-Notch Impact Test Results

Cold Work Aging Temperature Aging Time Impact Energy (ft-lb)*
(%) (°F) (hr) Longitudinal Transverse
0 1050 10 116 128
1100 1 111 120
100 118 115
1150 10 112 124
25 1050 1 61 65
100 31 31
1100 10 38 38
10 36 40
10 38 38
1150 1 57 63
100 18 19
50 1050 10 21 21
1100 1 30 30
100 29 33
1150 10 14 15

*Average of three tests

Fracture Toughness

Room Temperature ASTM E1820 Tests

Material Condition Specimen Jc (lbs/in) KJC (ksi.in1/2)
Cold-worked (52-53%) 1 921 174
2 1151 195
3 897 172

4.25 in (108 mm) OD x 2.25 in (57 mm) ID Tube Pre-Cracked Half-T Compact Tension [C(T)] Specimens Located at 120° Increments

Hardness

Material Condition Hardness, HRC*
Cold-worked (43-47%) Bar 42
Cold-worked (43-47%) Tube 42

*Average values HRC= Hardeness Rockwell “C”

Compressive Strength

Room Temperature Compressive Strength of 0.75 in Diameter Cold-worked (44%) Bar and Corresponding Tensile Data

Material Condition Compressive Yield Strength* Compressive Strength* Tensile Yield Strength* Tensile Strength*
ksi MPa ksi MPa ksi MPa ksi MPa
Cold-worked (44%) Bar 163 1124 219 1510 205 1413 210 1448

*Average from two tests

Resistance to Sour Gas Environments

Sour Gas Testing – NACE TM0177 Method A Tensile Test, Test Levels II and III, 720 hours, Applied Stress = 100% YS

Material Condition Heat Yield Strength(ksi) Coupled toCarbon Steel Not Coupled toCarbon Steel
Cold-Worked Heat 1 205 Pass Pass
Heat 2 191 Pass Pass
Heat 3 204 Pass Pass
Heat 4 233 Pass Pass
Heat 5 225 Pass Pass
Heat 6 223 Pass Pass
Heat 7 215 Pass Pass
Heat 8 222 Pass Pass

*Triplicate tests

Sour Gas Testing – NACE TM0177 Method C, 90-Day C-Ring Test,
Test Level VII:  25% NaCl, 500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2,
Elemental Sulfur = 1 g/l and 5 g/l**

Test Temperature: 401°F (205°C), Applied Stress = 100% YS
Material Condition: Cold-Worked

Heat Yield Strength(ksi) Result*
Heat 1 205 1 g/l S: Pass 5 g/l S: Pass
Heat 2 187 1 g/l S: Pass 5 g/l S: Pass
Heat 3 188 1 g/l S: Pass 5 g/l S: Pass

*Triplicate tests
**With stirring

Sour Gas Testing – NACE TM0177 Method C, 90-Day C-Ring Test, Test Level VII-Plus: 25% NaCl, 1000 psi (6.9 MPa) H2S + 1000 psi (6.9 MPa) CO2

Test Temperature: 401°F (205°C)
Material Condition: Cold-Worked

3 Passing Test Results
Heat Yield Strength(ksi)
Heat 1 205
Heat 2 187
Heat 3 188
Heat 4 233
Heat 5 225
Heat 6 223
 Heat 8  222 

Sour Gas Testing – NACE TM0198 Slow Strain Rate Tensile Test, Test Level VII:  25% NaCl,
500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2, Without (w/o) Elemental Sulfur

Test Temperature: 401°F (205°C)
Material Condition: Cold-Worked

Test Environment* Time to Failure (h) Elong. (%) R.A. (%) Time to Failure Ratio Elong. Ratio R.A. Ratio Secondary Cracking
Air 8.9 12.8 63.4 - - - -
Level VII w/o S 8.4 12.1 63.2 0.95 0.95 1 No

*Air – single test; Level VII w/o S – triplicate tests

Sour Gas Testing – NACE TM0198 Slow Strain Rate Tensile Test, Test Level VII:  25% NaCl,
500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2, With Elemental Sulfur

Test Temperature: 401°F (205°C)
Material Condition: Cold-Worked

Test Environment* Time to Failure (h) Elong. (%) R.A. (%) Time to Failure Ratio Elong. Ratio R.A. Ratio Secondary Cracking
Air 8.9 12.8 63.4 - - - -
Level VII w/S 8.2 11.7 62.4 0.92 0.91 0.98 No

*Air – single test; Level VII w/S – triplicate tests

Resistance to Hydrogen Embrittlement

Slow Strain Rate Tensile Test – Cold-worked Material

Environment Max. Load Normalized Factor Max. Load
lb kg  - h
Air 3997 1813 - 11.6
Air 4008 1818   - 14.1
3.5% NaCl 4020 1823 1.00 12.9
3.5% NaCl 3937 1786 0.98 11.1
3.5% NaCl @ -850 mV 3925 1780 0.98 10.9
3.5% NaCl @ -850 mV 4003 1816 1.00 13.6
3.5% NaCl @ -1000 mV 3956 1794 0.99 13.8
3.5% NaCl @ -1000 mV 3908 1773 0.98 10.9

Resistance to Acids

Corrosion Rates of Cold-worked (40%) Sheet in Aqueous Solutions of Common Acids

Acid Concentration Temperature Corrosion Rate
wt% °F °C mpy mm/y
Hydrochloric 1 Boiling 0.4 0.01
5 175 79 30.0 0.76
10 100 38 <0.1 <0.01
20 100 38 7.2 0.18
Hydrobromic 5 200 93 1.7 0.04
Nitric 20 Boiling 1.7 0.04
40 175 79 2.1 0.05
60 175 79 4.7 0.12
Hydrofluoric 5 125 52 18.8 0.48
Phosphoric 60 Boiling 4.7 0.12
Chromic 10 150 66 5.1 0.13
Sulfuric 10 200 93 3.8 0.10
20 200 93 2.8 0.07
30 200 93 6.8 0.17
40 175 79 1.1 0.03
50 175 79 13.1 0.33
60 150 66 0.31 0.01
70 150 66 3.1 0.08
80 150 66 4.8 0.12
90 150 66 1.3 0.03
ASTM G-28A* - Boiling 42.4 1.08
ASTM G-28B** - Boiling 9.8 0.25

*ASTM G-28A = 50% H2SO4 + 42 g/l Fe2(SO4)3
**ASTM G-28B = 23% H2SO4 + 1.2% HCl + 1% Fe3Cl + 1% CuCl2

Dynamic Modulus

High-Cycle Fatigue

Material: 0.5 in Diameter 43% Cold Worked Bar (0.2%YS – 191 ksi, UTS – 196 ksi, %EL – 18, %RA – 66)
Rotating Bend Fatigue Testing, RR Moore Rotating 4-Point Bend
R = -1.0 Stress Ratio, 167 Hz, Room Temperature

Hardness Profile

HRC = Hardness, Rockwell C Scale

Diameter % Cold-Worked Yield Strength (ksi) Hardness (HRC)
1" Below Surface Mid-Radius 1" Below Surface Mid-Radius
7.5 50 185.5 180.3 - -
8 50 175.4 - - -
8.25 40 168.1 166.2 38.6 36.1
10 30 162.3 149.8 40.0 35.0

HRC= Hardness Rockwell “C”

Thermal Stability

Effects of Thermal Exposure on Tensile Properties of 0.5 in Diameter,

Cold-worked (43%) Bar

Initial MaterialCondition Thermal Exposure Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation R.A.
°F °C ksi MPa ksi MPa % %
43% Cold-worked Bar - RT RT 195.1 1345 200.4 1382 18.0 65.2
500 260 181.0 1248 181.1 1249 14.1 60.8
43% Cold-worked Bar 500°F/4000h/AC RT RT 205.8 1419 212.6 1466 16.0 62.6
500 260 176.0 1214 178.5 1231 15.0 61.1
43% Cold-worked Bar 500°F/8000h/AC RT RT 209.9 1447 209.9 1447 16.0 60.7
200 93 192.8 1329 192.8 1329 17.0 63.8
500 260 186.6 1287 186.6 1287 13.4 60.7

AC=Air Cool
RT= Room Temperature
R.A.= Reduction of Area

Effects of Thermal Exposure on Impact Strength of 1 in Diameter, Cold-worked (44%) Bar

Initial Material Condition Thermal Exposure Charpy Impact Energy
ft.ibf J
RT -75°F (-59°C)
44% Cold-worked - 146 (198) 153 (207)
44% Cold-worked 500°F/4000h/AC 136 (184) 135 (183)

AC= Air Cooled
RT= Room Temperature

Resistance of Welds to Sour Gas Environments

Sour Gas Testing – NACE TM0177 Test Levels II and III, Method A, Solution A, Applied Stress = 100% YS, Material Condition: All Weld Metal, As Welded

Heat Yield Strength (ksi) Coupling Result*
1 62 Coupled to Carbon Steel Pass
NOT Coupled to Carbon Steel Pass
2 65 Coupled to Carbon Steel Pass
NOT Coupled to Carbon Steel Pass
3 63 Coupled to Carbon Steel Pass
NOT Coupled to Carbon Steel Pass

*Triplicate tests

Sour Gas Testing – NACE TM0198 Slow Strain Rate Tensile, Level VII, Test Environment: 25% NaCl, 500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2, 401°F (205°C),
Material Condition: All Weld Metal, As Welded

Heat Environment* Time to Failure (h) Elongation (%) R.A. (%) Time to Failure Ratio Elongation Ratio R.A. Ratio Secondary Cracking
1 Air 33.3 47.9 63.5 - - - -
Level VII w/o S 32.1 46.2 61.2 0.96 0.96 0.96 No
2 Air 28.4 40.9 58.4 -   - - -
Level VII w/o S 26.5 38.2 55.7 0.93 0.93 0.95 No
3 Air 28.9 41.6 59.7 - - - -
Level VII w/o S 28.5 41.2 61.0 0.99 0.99 1.02 No

*Air – duplicate tests, Level VII w/o sulfur – triplicate tests
R.A.= Reduction of Area

Sour Gas Testing – NACE TM0198 Slow Strain Rate Tensile, Level VII, Test Environment: 25% NaCl, 500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2,
Material Condition: All Weld Metal, As Welded, Heat 1

Test Temperature Environment* Time to Failure (h) Elongation (%) R.A. (%) Time to Failure Ratio Elongation Ratio R.A. Ratio Secondary Cracking
350°F (177°C)** Air 35.2 50.7 64.1 - - - -
Test Environ. + Sulfur 34.2 49.3 63.6 0.97 0.97 0.99 No
400°F (204°C)*** Air 35.8 51.5 63.1 - - - -
Test Environ. + Sulfur 34.5 49.6 56.1 0.96 0.96 0.89 No
500°F (260°C)*** Air 33.7 48.5 64.3 - - - -
Test Environment 33.7 48.6 61.0 1.0 1.0 0.95 No
550°F (288°C)** Air 34.1 49.1 65.7 - - - -
Test Environment 32.2 46.3 61.7 0.94 0.94 0.94 No

*Air – single test; Test Environment – **duplicate tests, ***triplicate tests

Weld Mechanical Properties

C-22HS® alloy Room Temperature Transverse Weld Tensile Test Results,
As-Welded Condition

Test 0.2% YieldStrength (ksi) Ultimate TensileStrength (ksi) Elong.(%) RA(%) FailureLocation
GTAW - 0.125 in (3.2 mm) sheet, autogenous w/ cover pass
A 66.2 115.3 31.5 - Weld Metal
B 64.6 119.2 41 - Weld Metal
C 65.3 113.3 30.3 - Weld Metal
Avg. 65.4 115.9 34.3 - -
GTAW - 0.5 in (12.7 mm) plate, w/ 0.125 in (3.2 mm) dia. filler metal
A 67.9 115.8 45.6 51.3 Weld Metal
B 68.3 114.9 44.1 62.6 Weld Metal
C 66.4 113.4 42.3 54.8 Weld Metal
Avg. 67.5 114.7 44 56.2 -
GMAW - 0.5 in (12.7 mm) plate, w/ 0.045 in (1.1 mm) dia. filler metal
A 64.3 114.2 46.2 48 Weld Metal
B 63.3 113.7 46 43.1 Weld Metal
C 64.8 113.8 46.4 47 Weld Metal
Avg. 64.1 113.9 46.2 46 -
GMAW – 1.0 in (25.4 mm) plate, w/ 0.045 in (1.1 mm) dia. filler metal
A 63.3 113.4 40.4 49.8 Weld Metal
B 63.3 111.9 38.8 55.9 Weld Metal
C 62 114 38.9 53.2 Weld Metal
Avg. 62.9 113.1 39.4 53 -

C-22HS® alloy Room Temperature All-Weld-Metal Tensile Test Results,
As-Welded Condition

Heat Sample 0.2% Yield Strength (ksi) Ultimate Tensile Strength (ksi) Elong. (%) RA (%)
1 GTAW Longitudinal 66.4 102.7 39.2 49.1
GMAW Longitudinal 66 105 53.1 53
2 GMAW Longitudinal 64.8 106.1 48.4 59.7
65.6 106.9 50.7 56.2
GMAWTransverse 63.1 103.5 46.8 62.7
62.7 104.6 54.6 63.9
3 GMAW Longitudinal 71.2 112 49.6 56.3
62.9 106.7 47.9 53.4
GMAW Transverse 65 105.2 45.9 58.3
64.9 105.9 50.5 57.5

C-22HS Alloy Weld Metal Charpy V-Notch Impact Test Results,
As-Welded Condition

Test Temperature Impact Energy (ft-lb)
Test 1 Test 2 Test 3 Avg.
GTAW - 0.5 in (12.7 mm) plate, w/ 0.125 in (3.2 mm) dia. filler metal
RT 154.2 166.2* 178.6* 166.3
-320°F (-196°C) 127.4 131.6 120.1 126.3
GMAW - 0.5 in (12.7 mm) plate, w/ 0.045 in (1.1 mm) dia. filler metal
RT 143.7 147 143.9 145.2
-320°F (-196°C) 117.3 109.8 122.2 116.4
GMAW – 1.0 in (25.4 mm) plate, w/ 0.045 in (1.1 mm) dia. filler metal
RT 129.9 163.4* 149.5 147.6
-320°F (-196°C) 118.4 122.8 126.6 122.6

*Test sample did not break

Specifications

Specifications

HASTELLOY® C-22HS® alloy (N07022)
Billet, Rod & Bar B 637
Coated Electrodes -
Bare Welding Rods & Wire -
Seamless Pipe & Tube B 983
Welded Pipe & Tube -
Fittings -
Forgings B 637
DIN -
TÜV -
Others NACE MR0175

Disclaimer

Haynes International makes all reasonable efforts to ensure the accuracy and correctness of the data displayed on this site but makes no representations or warranties as to the data’s accuracy, correctness or reliability. All data are for general information only and not for providing design advice. Alloy properties disclosed here are based on work conducted principally by Haynes International, Inc. and occasionally supplemented by information from the open literature and, as such, are indicative only of the results of such tests and should not be considered guaranteed maximums or minimums.  It is the responsibility of the user to test specific alloys under actual service conditions to determine their suitability for a particular purpose.

For specific concentrations of elements present in a particular product and a discussion of the potential health affects thereof, refer to the Safety Data Sheets supplied by Haynes International, Inc.  All trademarks are owned by Haynes International, Inc., unless otherwise indicated.

Alloy Brochure

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