HASTELLOY® C-22® alloy
Principal Features
Enhanced versatility and exceptional resistance to chloride-induced pitting
HASTELLOY® C-22® alloy (UNS N06022) is one of the well-known and well-proven nickel-chromium-molybdenum materials, the chief attributes of which are resistance to both oxidizing and non-oxidizing chemicals, and protection from pitting, crevice attack, and stress corrosion cracking. Its high chromium content provides much higher resistance to oxidizing media than the family standard, C-276 alloy, and imparts exceptional resistance to chloride-induced pitting, an insidious and unpredictable form of attack, to which the stainless steels are prone.
Like other nickel alloys, HASTELLOY® C-22® alloy is very ductile, exhibits excellent weldability, and is easily fabricated into industrial components. It is available in the form of plates, sheets, strips, billets, bars, wires, pipes, tubes, and covered electrodes. Typical chemical process industry (CPI) applications include reactors, heat exchangers, and columns.
*Please contact our technical support team if you have technical questions about this alloy.
Nominal Composition
| Weight % | |
| Nickel | 56 Balance |
| Chromium | 22 |
| Molybdenum | 13 |
| Iron | 3 |
| Cobalt | 2.5 max. |
| Tungsten | 3 |
| Manganese | 0.5 max. |
| Silicon | 0.08 max. |
| Carbon | 0.01 max. |
| Vanadium | 0.35 max. |
| Copper | 0.5 max. |
Iso-Corrosion Diagrams
Each of these iso-corrosion diagrams was constructed using numerous corrosion rate values, generated at different acid concentrations and temperatures. The blue line represents those combinations of acid concentration and temperature at which a corrosion rate of 0.1 mm/y (4 mils per year) is expected, based on laboratory tests in reagent grade acids. Below the line, rates under 0.1 mm/y are expected. Similarly, the red line indicates the combinations of acid concentration and temperature at which a corrosion rate of 0.5 mm/y (20 mils per year) is expected. Above the line, rates over 0.5 mm/y are expected. Between the blue and red lines, corrosion rates are expected to fall between 0.1 and 0.5 mm/y.
Comparative 0.1 mm/y Line Plots
To compare the performance of HASTELLOY C-22 alloy with that of other materials, it is useful to plot the 0.1 mm/y lines. In the following graphs, the lines for C-22 alloy are compared with those of two popular, austenitic stainless steels (316L and 254SMO), and a lower-molybdenum nickel alloy (625), in hydrochloric and sulfuric acids. The tests in hydrochloric acid were limited to a concentration of 20% (the azeotrope). At hydrochloric acid concentrations above about 5%, C-22 alloy provides a quantum improvement over the stainless steels, and offers much greater resistance hydrochloric acid than 625 alloy in the concentration range 8 to 20%.
Selected Corrosion Data
Hydrobromic Acid
| Conc. | 50°F | 75°F | 100°F | 125°F | 150°F | 175°F | 200°F | 225°F | Boiling |
| 10°C | 24°C | 38°C | 52°C | 66°C | 79°C | 93°C | 107°C | ||
| 2.5 | – | – | – | – | – | – | – | – | 0.02 |
| 5 | – | – | – | – | – | – | 0.01 | – | 0.76 |
| 7.5 | – | – | – | – | – | 0.01 | 0.45 | – | – |
| 10 | – | – | – | – | – | 0.01 | 1.50 | – | – |
| 15 | – | – | – | 0.01 | <0.01 | 0.88 | – | – | – |
| 20 | – | – | – | 0.01 | 0.46 | 0.80 | – | – | – |
| 25 | – | – | <0.01 | 0.20 | 0.29 | 0.58 | 0.97 | – | – |
| 30 | – | – | 0.11 | 0.23 | 0.29 | 0.59 | 1.12 | – | – |
| 40 | – | – | 0.07 | 0.13 | 0.21 | 0.34 | 0.66 | – | – |
All corrosion rates are in millimeters per year (mm/y); to convert to mils (thousandths of an inch) per year, divide by 0.0254.
Data are from Corrosion Laboratory Jobs 15-02, 27-02, and 37-02.
All tests were performed in reagent grade acids under laboratory conditions; field tests are encouraged prior to industrial use.
Hydrochloric Acid
| Conc. | 50°F | 75°F | 100°F | 125°F | 150°F | 175°F | 200°F | 225°F | Boiling |
| 10°C | 24°C | 38°C | 52°C | 66°C | 79°C | 93°C | 107°C | ||
| 1 | – | – | – | – | – | – | 0.01 | – | 0.06 |
| 1.5 | – | – | – | – | – | – | – | – | – |
| 2 | – | – | – | – | – | – | – | – | – |
| 2.5 | – | – | – | – | – | – | – | – | – |
| 3 | – | – | – | – | – | – | – | – | – |
| 3.5 | – | – | – | – | – | – | – | – | – |
| 4 | – | – | – | – | – | – | – | – | – |
| 4.5 | – | – | – | – | – | – | – | – | – |
| 5 | – | – | <0.01 | – | 0.44 | 1.44 | 3.02 | – | 8.99 |
| 7.5 | – | – | – | – | – | – | – | – | – |
| 10 | – | – | 0.01 | 0.28 | 0.98 | 1.99 | 4.39 | – | 11.68 |
| 15 | – | – | – | – | 0.98 | 1.91 | – | – | 11.02 |
| 20 | – | – | 0.20 | 0.32 | 0.90 | 1.72 | 3.38 | – | 9.73 |
All corrosion rates are in millimeters per year (mm/y); to convert to mils (thousandths of an inch) per year, divide by 0.0254.
Data are from Corrosion Laboratory Jobs 442-82 and 176-83.
All tests were performed in reagent grade acids under laboratory conditions; field tests are encouraged prior to industrial use.
Nitric Acid
| Conc. | 50°F | 75°F | 100°F | 125°F | 150°F | 175°F | 200°F | 225°F | Boiling |
| 10°C | 24°C | 38°C | 52°C | 66°C | 79°C | 93°C | 107°C | ||
| 10 | – | – | – | – | <0.01 | – | 0.01 | – | 0.01 |
| 20 | – | – | – | – | 0.01 | – | 0.02 | – | 0.06 |
| 30 | – | – | – | – | 0.01 | – | 0.02 | – | 0.13 |
| 40 | – | – | – | – | 0.02 | 0.03 | 0.09 | – | 0.26 |
| 50 | – | – | – | – | – | 0.05 | 0.14 | 0.33 | 0.59 |
| 60 | – | – | – | – | 0.06 | 0.08 | 0.19 | 0.57 | 1.09 |
| 70 | – | – | – | – | 0.05 | 0.11 | 0.33 | 0.71 | 2.53 |
All corrosion rates are in millimeters per year (mm/y); to convert to mils (thousandths of an inch) per year, divide by 0.0254.
Data are from Corrosion Laboratory Jobs 443-82 and 47-04.
All tests were performed in reagent grade acids under laboratory conditions; field tests are encouraged prior to industrial use.
Phosphoric Acid
| Conc. Wt.% | 125°F | 150°F | 175°F | 200°F | 225°F | 250°F | 275°F | 300°F | Boiling |
| 52°C | 66°C | 79°C | 93°C | 107°C | 121°C | 135°C | 149°C | ||
| 50 | – | – | – | – | – | – | – | – | 0.07 |
| 60 | – | – | – | – | 0.08 | – | – | – | 0.16 |
| 65 | – | – | – | – | – | – | – | – | – |
| 70 | – | – | – | – | 0.07 | 0.13 | – | – | 0.23 |
| 75 | – | – | – | – | 0.05 | 0.12 | – | – | 0.19 |
| 80 | – | – | – | – | 0.06 | 0.12 | 0.16 | – | 0.25 |
| 85 | – | – | – | – | 0.07 | 0.12 | 0.20 | – | 0.66 |
All corrosion rates are in millimeters per year (mm/y); to convert to mils (thousandths of an inch) per year, divide by 0.0254.
Data are from Corrosion Laboratory Jobs 444-82 and 46-04.
All tests were performed in reagent grade acids under laboratory conditions; field tests are encouraged prior to industrial use.
Sulfuric Acid
| Cont. | 75°F | 100°F | 125°F | 150°F | 175°F | 200°F | 225°F | 250°F | 275°F | 300°F | 350°F | Boiling |
| 24°C | 38°C | 52°C | 66°C | 79°C | 93°C | 107°C | 121°C | 135°C | 149°C | 177°C | ||
| 1 | – | – | – | – | – | – | – | – | – | – | – | – |
| 2 | – | – | – | – | – | 0.01 | – | – | – | – | – | 0.13 |
| 3 | – | – | – | – | – | – | – | – | – | – | – | – |
| 4 | – | – | – | – | – | – | – | – | – | – | – | – |
| 5 | – | – | – | <0.01 | 0.01 | 0.03 | – | – | – | – | – | 0.23 |
| 10 | – | – | – | – | 0.02 | 0.04 | – | – | – | – | – | 0.29 |
| 20 | – | – | – | 0.01 | 0.03 | 0.28 | – | – | – | – | – | 0.83 |
| 30 | – | – | – | 0.01 | 0.09 | 0.68 | – | – | – | – | – | 1.89 |
| 40 | – | – | 0.01 | 0.01 | 0.31 | 0.87 | – | – | – | – | – | 3.99 |
| 50 | – | – | – | 0.02 | 0.40 | 0.77 | 2.18 | – | – | – | – | 9.98 |
| 60 | – | – | 0.01 | – | 0.67 | 0.95 | 2.69 | 7.62 | – | – | – | – |
| 70 | – | – | – | 0.28 | 0.56 | 0.94 | 3.07 | 14.94 | – | – | – | – |
| 80 | – | – | 0.09 | – | 1.44 | 2.16 | 3.68 | 3.58 | – | – | – | – |
| 90 | – | – | – | 0.34 | 0.89 | 1.80 | 6.27 | 4.24 | – | – | – | – |
| 96 | – | – | – | 0.10 | – | 1.10 | – | – | – | – | – | – |
All corrosion rates are in millimeters per year (mm/y); to convert to mils (thousandths of an inch) per year, divide by 0.0254.
Data are from Corrosion Laboratory Jobs 319-82, 445-82, and 19-14.
All tests were performed in reagent grade acids under laboratory conditions; field tests are encouraged prior to industrial use.
Reagent Grade Solutions, mm/y
| Chemical | Conc. | 100°F | 125°F | 150°F | 175°F | 200°F | Boiling |
| 38°C | 52°C | 66°C | 79°C | 93°C | |||
| Acetic Acid | 99 | – | – | – | – | – | 0.00 |
| Formic Acid | 88 | – | – | – | – | – | <0.01 |
| Hydrobromic Acid | 2.5 | – | – | – | – | – | 0.02 |
| 5 | – | – | – | – | – | 0.76 | |
| 7.5 | – | – | – | 0.01 | – | – | |
| 10 | – | – | – | 0.01 | – | – | |
| 15 | – | 0.01 | <0.01 | 0.88 | – | – | |
| 20 | – | 0.01 | 0.46 | 0.80 | – | – | |
| 25 | <0.01 | 0.20 | 0.29 | 0.58 | – | – | |
| 30 | 0.11 | 0.23 | 0.29 | 0.59 | – | – | |
| 40 | 0.07 | 0.13 | 0.21 | 0.34 | – | – | |
| Hydrochloric Acid | 1 | – | – | – | – | 0.01 | 0.06 |
| 5 | <0.01 | – | 0.44 | – | – | – | |
| 7.5 | – | – | – | – | – | – | |
| 10 | 0.01 | 0.28 | 0.98 | – | – | – | |
| 15 | – | – | – | – | – | – | |
| 20 | 0.20 | 0.32 | 0.90 | – | – | – | |
| Hydrofluoric Acid* | 5 | 0.04 | 0.15 | 0.47 | 0.58 | – | – |
| 10 | 0.09 | 0.33 | 0.64 | 0.78 | – | – | |
| 20 | 0.22 | 0.53 | 0.95 | 1.65 | – | – | |
| Nitric Acid | 10 | – | – | <0.01 | – | 0.01 | 0.01 |
| 20 | – | – | 0.01 | – | 0.02 | 0.06 | |
| 30 | – | – | 0.01 | – | 0.02 | 0.13 | |
| 40 | – | – | 0.02 | – | 0.09 | 0.26 | |
| 50 | – | – | – | – | 0.14 | 0.59 | |
| 60 | – | – | 0.06 | – | 0.19 | 1.09 | |
| 65 | – | – | – | – | – | – | |
| 70 | – | – | 0.05 | – | 0.33 | 2.53 | |
| Phosphoric Acid | 50 | – | – | – | – | – | 0.07 |
| 60 | – | – | – | – | – | 0.16 | |
| 70 | – | – | – | – | – | 0.23 | |
| 75 | – | – | – | – | – | 0.19 | |
| 80 | – | – | – | – | – | 0.25 | |
| 85 | – | – | – | – | – | 0.66 | |
| Sulfuric Acid | 10 | – | – | – | 0.02 | 0.04 | 0.29 |
| 20 | – | – | 0.01 | 0.03 | 0.28 | 0.83 | |
| 30 | – | – | 0.01 | 0.09 | 0.68 | – | |
| 40 | – | – | 0.01 | 0.31 | 0.87 | – | |
| 50 | – | – | 0.02 | 0.40 | 0.77 | – | |
| 60 | – | – | – | 0.67 | 0.95 | – | |
| 70 | – | – | 0.28 | 0.56 | 0.94 | – | |
| 80 | – | – | – | 1.44 | 2.16 | – | |
| 90 | – | – | 0.34 | 0.89 | 1.80 | – | |
| 96 | – | – | 0.10 | – | 1.10 | – |
*Hydrofluoric acid can also induce internal attack of nickel alloys; these values represent only external attack.
Resistance to Pitting and Crevice Corrosion
HASTELLOY® C-22® alloy exhibits very high resistance to chloride-induced pitting and crevice attack, forms of corrosion to which the austenitic stainless steels are particularly prone. To assess the resistance of alloys to pitting and crevice attack, it is customary to measure their Critical Pitting Temperatures and Critical Crevice Temperatures in acidified 6 wt.% ferric chloride, in accordance with the procedures defined in ASTM Standard G 48. These values represent the lowest temperatures at which pitting and crevice attack are encountered in this solution, within 72 hours. For comparison, the values for 316L, 254SMO, 625, C-22® and C-276 alloys are as follows:
| Alloy | Critical Pitting Temperature in Acidified 6% FeCl3 | Critical Crevice Temperaturein Acidified 6% FeCl3 | ||
| °F | °F | °F | °F | |
| 316L | 59 | 15 | 32 | 0 |
| 254SMO | 140 | 60 | 86 | 30 |
| 625 | 212 | 100 | 104 | 40 |
| C-276 | >302 | >150 | 131 | 55 |
| C-22® | >302 | >150 | 176 | 80 |
Other chloride-bearing environments, notably Green Death (11.5% H2SO4 + 1.2% HCl + 1% FeCl3 + 1% CuCl2) and Yellow Death (4% NaCl + 0.1% Fe2(SO4)3 + 0.021M HCl), have been used to compare the resistance of various alloys to pitting and crevice attack (using tests of 24 hours duration). In Green Death, the lowest temperature at which pitting has been observed in C-22® alloy is 120°C (considerably higher than that of C-276, i.e. boiling). In Yellow Death, C-22® alloy has not exhibited pitting, even at the maximum test temperature (150°C).The Critical Crevice Temperature of C-22® alloy in Yellow Death is 75°C (as compared with 60°C for C-276 alloy).
Resistance to Stress Corrosion Cracking
One of the chief attributes of the nickel alloys is their resistance to chloride-induced stress corrosion cracking. A common solution for assessing the resistance of materials to this extremely destructive form of attack is boiling 45% magnesium chloride (ASTM Standard G 36), typically with stressed U-bend samples. As is evident from the following results, the three nickel alloys (C-22®, C-276 and 625) are much more resistant to this form of attack than the comparative, austenitic stainless steels. The tests were stopped after 1,008 hours (six weeks).
| Alloy | Time to Cracking |
| 316L | 2 h |
| 254SMO | 24 h |
| 625 | No Cracking in 1,008 h |
| C-276 | No Cracking in 1,008 h |
| C-22® | No Cracking in 1,008 h |
Resistance to Seawater Crevice Corrosion
Seawater is probably the most common aqueous salt solution. Not only is it encountered in marine transportation and offshore oil rigs, but it is also used as a coolant in coastal facilities. Listed are data generated as part of a U.S. Navy study at the LaQue Laboratories in Wrightsville Beach, North Carolina (and published by D.M. Aylor et al, Paper No. 329, CORROSION 99, NACE International, 1999). Crevice tests were performed in both still (quiescent) and flowing seawater, at 29°C, plus or minus 3°C. Two samples (A & B) of each alloy were tested in still water for 180 days, and likewise in flowing water. Each sample contained two possible crevice sites. The results indicate that C-22® alloy is very resistant to crevice corrosion in seawater.
| Alloy | Quiescent | Flowing | ||
| No. of Sites Attacked | Maximum Depth | No. of Sites Attacked | Maximum Depth | |
| 316L | A:2, B:2 | A:1.33, B:2.27 | A:2, B:2 | A:0.48, B:0.15 |
| 254SMO | A:2, B:2 | A:0.76, B:1.73 | A:2, B:2 | A:0.01, B:<0.01 |
| 625 | A:1, B:2 | A:0.18, B:0.04 | A:2, B:2 | A:<0.01, B:<0.01 |
| C-276 | A:1, B:1 | A:0.10, B:0.13 | A:0, B:0 | A:0, B:0 |
| C-22® | A:0, B:0 | A:0, B:0 | A:0, B:0 | A:0, B:0 |
Corrosion Resistance of Welds
To assess the resistance of welds to corrosion, Haynes International has chosen to test all-weld-metal samples, taken from the quadrants of cruciform assemblies, created using multiple gas metal arc (MIG) weld passes. Predictably, the inhomogeneous nature of weld microstructures leads to higher corrosion rates (than with homogeneous, wrought products). Nevertheless, HASTELLOY® C-22® alloy exhibits excellent resistance to the key, inorganic acids, even in welded form, as shown in the following table:
| Chemical | Concentration | Temperature | Corrosion Rate | ||||
| wt.% | °F | °C | Weld Metal | Wrought Base Metal | |||
| mpy | mm/y | mpy | mm/y | ||||
| H2SO4 | 30 | 150 | 66 | 0.6 | 0.02 | 0.4 | 0.01 |
| H2SO4 | 50 | 150 | 66 | 9.3 | 0.24 | 0.8 | 0.02 |
| H2SO4 | 70 | 150 | 66 | 10.3 | 0.26 | 11.0 | 0.28 |
| H2SO4 | 90 | 150 | 66 | 18.5 | 0.47 | 13.4 | 0.34 |
| HCl | 5 | 100 | 38 | <0.1 | <0.01 | <0.1 | <0.01 |
| HCl | 10 | 100 | 38 | <0.1 | <0.01 | 0.4 | 0.01 |
| HCl | 15 | 100 | 38 | 11.1 | 0.28 | 9.4 | 0.24 |
| HCl | 20 | 100 | 38 | 10.2 | 0.26 | 7.9 | 0.20 |
Physical Properties
| Physical Property | British Units | Metric Units | ||
| Density | RT |
0.314 lb/in3 |
RT |
8.69 g/cm3 |
| Electrical Resistivity | RT | 44.9 μohm.in | RT | 1.14 μohm.m |
| 200°F | 48.0 μohm.in | 100°C | 1.23 μohm.m | |
| 400°F | 48.8 μohm.in | 200°C | 1.24 μohm.m | |
| 600°F | 49.3 μohm.in | 300°C | 1.25 μohm.m | |
| 800°F | 49.7 μohm.in | 400°C | 1.26 μohm.m | |
| 1000°F | 50.1 μohm.in | 500°C | 1.27 μohm.m | |
| – | – | 600°C | 1.28 μohm.m | |
| Thermal Conductivity | 100°F |
69 Btu.in/h.ft2.°F |
50°C | 10.1 W/m.°C |
| 200°F |
76 Btu.in/h.ft2.°F |
100°C | 11.1 W/m.°C | |
| 400°F |
94 Btu.in/h.ft2.°F |
200°C | 13.4 W/m.°C | |
| 600°F |
110 Btu.in/h.ft2.°F |
300°C | 15.5 W/m.°C | |
| 800°F |
125 Btu.in/h.ft2.°F |
400°C | 17.5 W/m.°C | |
| 1000°F |
139 Btu.in/h.ft2.°F |
500°C | 19.5 W/m.°C | |
| – | – | 600°C | 21.3 W/m.°C | |
| Thermal Diffusivity | RT |
0.004 in2/s |
RT |
0.027 cm2/s |
| 200°F |
0.005 in2/s |
100°C |
0.030 cm2/s |
|
| 400°F |
0.005 in2/s |
200°C |
0.035 cm2/s |
|
| 600°F |
0.006 in2/s |
300°C |
0.039 cm2/s |
|
| 800°F |
0.007 in2/s |
400°C |
0.042 cm2/s |
|
| 1000°F |
0.007 in2/s |
500°C |
0.046 cm2/s |
|
| – | – | 600°C |
0.048 cm2/s |
|
| Mean Coefficient of Thermal Expansion | 75-200°F | 6.9 μin/in.°F | 24-100°C | 12.4 μm/m.°C |
| 75-400°F | 6.9 μin/in.°F | 24-200°C | 12.4 μm/m.°C | |
| 75-600°F | 7.0 μin/in.°F | 24-300°C | 12.6 μm/m.°C | |
| 75-800°F | 7.4 μin/in.°F | 24-400°C | 13.1 μm/m.°C | |
| 75-1000°F | 7.7 μin/in.°F | 24-500°C | 13.7 μm/m.°C | |
| 75-1200°F | 8.1 μin/in.°F | 24-600°C | 14.3 μm/m.°C | |
| 75-1400°F | 8.5 μin/in.°F | 24-700°C | 14.9 μm/m.°C | |
| 75-1600°F | 8.8 μin/in.°F | 24-800°C | 15.5 μm/m.°C | |
| 75-1800°F | 9.0 μin/in.°F | 24-900°C | 15.9 μm/m.°C | |
| Specific Heat | 100°F | 0.098 Btu/lb.°F | 50°C | 414 J/kg.°C |
| 200°F | 0.101 Btu/lb.°F | 100°C | 423 J/kg.°C | |
| 400°F | 0.106 Btu/lb.°F | 200°C | 444 J/kg.°C | |
| 600°F | 0.111 Btu/lb.°F | 300°C | 460 J/kg.°C | |
| 800°F | 0.114 Btu/lb.°F | 400°C | 476 J/kg.°C | |
| 1000°F | 0.118 Btu/lb.°F | 500°C | 485 J/kg.°C | |
| – | – | 600°C | 514 J/kg.°C | |
| Dynamic Modulus of Elasticity | RT |
29.9 x 106psi |
RT | 206 GPa |
| 200°F |
29.4 x 106psi |
200°C | 197 GPa | |
| 400°F |
28.5 x 106psi |
300°C | 191 GPa | |
| 600°F |
27.6 x 106psi |
400°C | 185 GPa | |
| 800°F |
26.6 x 106psi |
500°C | 179 GPa | |
| 1000°F |
25.7 x 106psi |
600°C | 174 GPa | |
| 1200°F |
24.8 x 106psi |
700°C | 168 GPa | |
| 1400°F |
23.6 x 106psi |
800°C | 160 GPa | |
| 1600°F |
22.4 x 106psi |
900°C | 152 GPa | |
| 1800°F |
21.1 x 106psi |
1000°C | 144 GPa | |
| Melting Range | 2475-2550°F | – | 1357-1399°C | – |
RT= Room Temperature
Impact Strength
| Test Temperature | Impact Strength | ||
| °F | °C | ft-lbf | J |
| RT | RT | 419 | 568 |
| -320 | -196 | 346 | 469 |
Impact strengths were generated using Charpy V-notch samples, machined from mill annealed plate.
Tensile Strength and Elongation
| Form | Test Temperature | Thickness/Bar Diameter | 0.2% Offset Yield Strength | Ultimate Tensile Strength | Elongation | ||||
| °F | °C | in | mm | ksi | MPa | ksi | MPa | % | |
| Sheet | RT | RT | 0.028-0.125 | 0.7-3.2 | 59 | 407 | 116 | 800 | 57 |
| Sheet | 200 | 93 | 0.028-0.125 | 0.7-3.2 | 54 | 372 | 110 | 758 | 58 |
| Sheet | 400 | 204 | 0.028-0.125 | 0.7-3.2 | 44 | 303 | 102 | 703 | 57 |
| Sheet | 600 | 316 | 0.028-0.125 | 0.7-3.2 | 42 | 286 | 98 | 676 | 62 |
| Sheet | 800 | 427 | 0.028-0.125 | 0.7-3.2 | 41 | 283 | 95 | 655 | 67 |
| Sheet | 1000 | 538 | 0.028-0.125 | 0.7-3.2 | 40 | 276 | 91 | 627 | 61 |
| Sheet | 1200 | 649 | 0.028-0.125 | 0.7-3.2 | 36 | 248 | 85 | 586 | 65 |
| Sheet | 1400 | 760 | 0.028-0.125 | 0.7-3.2 | 35 | 241 | 76 | 524 | 63 |
| Plate | RT | RT | 0.25-0.75 | 6.4-19.1 | 54 | 372 | 114 | 786 | 62 |
| Plate | 200 | 93 | 0.25-0.75 | 6.4-19.1 | 49 | 338 | 107 | 738 | 65 |
| Plate | 400 | 204 | 0.25-0.75 | 6.4-19.1 | 41 | 283 | 98 | 676 | 66 |
| Plate | 600 | 316 | 0.25-0.75 | 6.4-19.1 | 36 | 248 | 95 | 655 | 68 |
| Plate | 800 | 427 | 0.25-0.75 | 6.4-19.1 | 35 | 241 | 92 | 634 | 68 |
| Plate | 1000 | 538 | 0.25-0.75 | 6.4-19.1 | 34 | 234 | 88 | 607 | 67 |
| Plate | 1200 | 649 | 0.25-0.75 | 6.4-19.1 | 32 | 221 | 83 | 572 | 69 |
| Plate | 1400 | 760 | 0.25-0.75 | 6.4-19.1 | 31 | 214 | 76 | 524 | 68 |
| Bar | RT | RT | 0.5-2.0 | 12.7-50.8 | 52 | 359 | 111 | 765 | 70 |
| Bar | 200 | 93 | 0.5-2.0 | 12.7-50.8 | 45 | 310 | 105 | 724 | 73 |
| Bar | 400 | 204 | 0.5-2.0 | 12.7-50.8 | 38 | 262 | 96 | 662 | 74 |
| Bar | 600 | 316 | 0.5-2.0 | 12.7-50.8 | 34 | 234 | 92 | 634 | 79 |
| Bar | 800 | 427 | 0.5-2.0 | 12.7-50.8 | 31 | 214 | 89 | 614 | 79 |
| Bar | 1000 | 538 | 0.5-2.0 | 12.7-50.8 | 29 | 200 | 84 | 579 | 80 |
| Bar | 1200 | 649 | 0.5-2.0 | 12.7-50.8 | 28 | 193 | 80 | 552 | 80 |
| Bar | 1400 | 760 | 0.5-2.0 | 12.7-50.8 | 29 | 200 | 72 | 496 | 77 |
Values are averages from numerous tests
RT= Room Temperature
Hardness
| Form | Hardness, HRBW | Typical ASTM Grain Size |
| Sheet | 88 | 3.5 – 5.5 |
| Plate | 88 | 0 – 4.5 |
| Bar | 84 | 1 – 3.5 |
All samples tested in solution-annealed condition.
HRBW = Hardness Rockwell “B”, Tungsten Indentor.
Welding and Fabrication
HASTELLOY® C-22® alloy is very amenable to the Gas Metal Arc (GMA/MIG), Gas Tungsten Arc (GTA/TIG), and Shielded Metal Arc (SMA/Stick) welding processes. For matching filler metals (i.e. solid wires and coated electrodes) that are available for these processes, and welding guidelines, please click here.
Wrought products of HASTELLOY® C-22® alloy are supplied in the Mill Annealed (MA) condition, unless otherwise specified. This solution annealing procedure has been designed to optimize the alloy’s corrosion resistance and ductility. Following all hot forming operations, the material should be re-annealed, to restore optimum properties. The alloy should also be re-annealed after any cold forming operations that result in an outer fiber elongation of 7% or more. The annealing temperature for HASTELLOY® C-22® alloy is 1121°C (2050°F), and water quenching is advised (rapid air cooling is feasible with structures thinner than 10 mm (0.375 in). A hold time at the annealing temperature of 10 to 30 minutes is recommended, depending on the thickness of the structure (thicker structures need the full 30 minutes). For more details concerning the heat treatment of HASTELLOY® C-22® alloy, please click here.
HASTELLOY® C-22® alloy can be hot forged, hot rolled, hot upset, hot extruded, and hot formed. However, it is more sensitive to strain and strain rates than the austenitic stainless steels, and the hot working temperature range is quite narrow. For example, the recommended start temperature for hot forging is 1232°C (2250°F) and the recommended finish temperature is 954°C (1750°F). Moderate reductions and frequent re-heating provide the best results, as described here. This reference also provides guidelines for cold forming, spinning, drop hammering, punching, and shearing. The alloy is stiffer than most austenitic stainless steels, and more energy is required during cold forming. Also, HASTELLOY® C-22® alloy work hardens more readily than most austenitic stainless steels, and may require several stages of cold work, with intermediate anneals.
While cold work does not usually affect the resistance of HASTELLOY® C-22® alloy to general corrosion, and to chloride-induced pitting and crevice attack, it can affect resistance to stress corrosion cracking. For optimum corrosion performance, therefore, the re-annealing of cold worked parts (following an outer fiber elongation of 7% or more) is important.
Specifications and Codes
Specifications
| HASTELLOY® C-22® alloy (N06022, W86022) | |
| Sheet, Plate & Strip | SB 575/B 575P= 43 |
| Billet, Rod & Bar | SB 574/B 574P= 43 |
| Coated Electrodes | SFA 5.11/ A5.11 (ENiCrMo-10)F=43 |
| Bare Welding Rods & Wire | SFA 5.14/ A5.14 (ERNiCrMo-10)F= 43 |
| Seamless Pipe & Tube | SB 622/B 622P= 43 |
| Welded Pipe & Tube | SB 619/B 619P= 43 |
| Fittings | SB 366/B 366P= 43 |
| Forgings | SB 564/B 564P= 43 |
| DIN | 17744 No. 2.4602 NiCr21Mo14W |
| TÜV | Werkstoffblatt 479Kennblatt 4535.00Kennblatt 4536.00Kennblatt 4534.01 |
| Others | NACE MR0175 |
Codes
| HASTELLOY® C-22® alloy (N06022, W86022) | |||
| ASME | Section l | 1250°F (677°C)1 | |
| Section lll | Class 1 | 800°F (427°C)1 | |
| Class 2 | 1250°F (677°C)2 | ||
| Class 3 | 1250°F (677°C)2 | ||
| Section Vlll | Div. 1 | 1250°F (677°C)1 | |
| Div. 2 | 1250°F (677°C)1 | ||
| Section Xll | 650°F (343°C)3 | ||
| B16.5 | 1250°F (677°C)4 | ||
| B16.34 | 1250°F (677°C)5 | ||
| B31.1 | 800°F (427°C)6 | ||
| B31.3 | 800°F (427°C)7 | ||
| VdTÜV (doc #) | 844°F (450ºC)8 ,#479 | ||
1Plate, Sheet, Bar, Forgings, fittings, welded pipe/tube, seamless pipe/tube
2Plate, Sheet, Bar, Forgings, welded pipe/tube, seamless pipe/tube
3Plate, Sheet, Bar, fittings, welded pipe/tube, seamless pipe/tube
4Plate, Forgings, fittings
5Plate, Bar, Forgings, seamless pipe/tube
6Plate, Sheet, fittings, welded pipe/tube, seamless pipe/tube
7Plate, Sheet, Forgings, fittings, welded pipe/tube, seamless pipe/tube
8Plate, Sheet, Bar, Forgings
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.