Hastelloy G Alloy Tubing Hastello G Alloy Pipe
Hastelloy G Alloy is an nickel-chromium-iron-molybdenum alloy developed for corrosion resistance in both oxidizing and reduceing media. Hastelloy G Alloy shows good resistance to sulfuric acids and phosphoric acids. Hastelloy G Alloy may further handle both acid and alkaline solutions.
Application of Hastelloy G Alloy
Hastelloy G Alloy is chosen for many chemical applications, particularly those involving sulfuric acids and phosphoric acids. Hastelloy G Alloy is widely used in flue gas desulfurization systems and in other types of pollution control equipment. Hastelloy G Alloy is also is used in pulp and paper industry equipment.
Hastelloy G Alloy Corrosion Resistance
Hastelloy G Alloy is an nickel-based alloy with excellent resistance to hot sulfuric and phosphoric acids. It withstands the corrosive effects of both oxidizing and reducing agents, and can handle both acid and alkaline solutions. The alloy has outstanding resistance to mixed acids, fluosilicic acid, sulfate compounds, contaminated nitric acid, wet flue gas desulfurization scrubber environmments and hydrofluoric acid. It resists pitting and has exceptional resistance to stress corrosion.
The resistance of Hastelloy G Alloy to the formation of grain boundary precipitates allows the alloy to be used as welded condition . In some applications, it’s necessary to solution annealing for optimum corrosion resistance after fabrication.
Chemical Composition of Hastelloy G Alloy
| Element | Min | Max |
| Molybdenum | 5.5 | 7.5 |
| Chromium | 21.0 | 23.5 |
| Iron | 18.0 | 21.0 |
| Tungsten | — | 1.00 |
| Cobalt | — | 2.50 |
| Carbon | — | 0.05 |
| Silicon | — | 1.00 |
| Manganese | 1.00 | 2.00 |
| Phosphorus | — | 0.04 |
| Sulfur | — | 0.03 |
| Nickel | Remainder | Remainder |
| Niobium + Tantalum | 1.75 | 2.50 |
| Copper | 1.50 | 2.50 |
Physical Properties of Hastelloy G Alloy
| Physical Properties | °F | British Units | °C | Metric Units |
| Density | 70 | 0.300 lb./in³ | 22 | 8.30 kg/dm³ |
| Melting Range | 2300- 2450 | 1260- 1343 | ||
| Mean Coefficient of Thermal Expansion | 70-200 | 7.5 microin./in.-°F | 21-93 | 13.5 X 10(-6)m/m-K |
| 70-400 | 7.7 microin./in.-°F | 21-204 | 13.9 X 10(-6)m/m-K | |
| 70-600 | 7.9 microin./in.-°F | 21-316 | 14.2 X 10(-6)m/m-K | |
| 70-800 | 8.3 microin./in.-°F | 21-427 | 14.9 X 10(-6)m/m-K | |
| 70-1000 | 8.7 microin./in.-°F | 21-538 | 15.7 X 10(-6)m/m-K | |
| 70-1200 | 9.1 microin./in.-°F | 21-649 | 16.4 X 10(-6)m/m-K | |
| Thermal Conductivity | 77 | 70 Btu-in/ft²-hr-°F | 25 | 10.1 W/m-K |
| 212 | 78 Btu-in/ft²-hr-°F | 100 | 11.2 W/m-K | |
| 392 | 89 Btu-in/ft²-hr-°F | 200 | 12.8 W/m-K | |
| 572 | 99 Btu-in/ft²-hr-°F | 300 | 14.3 W/m-K | |
| 752 | 110 Btu-in/ft²-hr-°F | 400 | 15.9 W/m-K | |
| 932 | 121 Btu-in/ft²-hr-°F | 500 | 17.4 W/m-K | |
| 1112 | 133 Btu-in/ft²-hr-°F | 600 | 19.2 W/m-K | |
| 1292 | 144 Btu-in/ft²-hr-°F | 700 | 20.8 W/m-K | |
| 1472 | 155 Btu-in/ft²-hr-°F | 800 | 22.3 W/m-K | |
| 1652 | 166 Btu-in/ft²-hr-°F | 900 | 23.9 W/m-K |
Dynamic Modulus of Elasticity of Hastelloy G Alloy
| Form | Condition | Test Temp, °F(°C) | Average Dynamic Modulus of Elasticity,10(6) psi (MPa) |
| Plate, 3/8″ thick | Solution Heat-treated | Room | 27.8 (200) |
| 400 (204) | 26.3 (181) | ||
| 600 (316) | 25.3 (174) | ||
| 800 (427) | 24.3 (168) | ||
| 1000 (538) | 23.4 (161) |
Hastelloy G Alloy Mechanical Properties
| Form | Test Temp °F(°C) | Ultimate Tensile Strength ksi (MPa) | Yield Strength at 0.2% offset ksi (MPa) | Elongation in 2″ percent | Reduction of Area, percent |
| Sheet, 0.125″ thick and under | Room 400 (204) 600 (316) 800 (427) 1000 (538) | 102.0 (703) 90.9 (627) 88.0 (607) 85.0 (586) 81.9 (565) | 46.2 (319) 37.4 (258) 35.8 (247) 33.4 (230) 32.8 (226) | 61 74 82 84 83 | 52 47 48 47 47 |
| Plate, 3/8 to 5/8″ thick | Room 400 (204) 600 (316) 800 (427) 1000 (538) | 99.6 (687) 87.9 (606) 84.4 (582) 82.0 (565) 76.3 (526) | 45.0 (310) 33.9 (234) 29.9 (206) 29.1 (201) 28.1 (194) | 62 63 68 70 73 | 57 52 52 52 57 |