Home / HASTELLOY® G-30® alloy

Principal FeaturesNominal CompositionResistance to "Wet Process"Iso-Corrosion DiagramsComparative 0 1 mm y Line PlotsSelected Corrosion DataResistance to Pitting and Crevice CorrosionResistance to Stress Corrosion CrackingCorrosion Resistance of WeldsPhysical PropertiesImpact StrengthTensile Strength and ElongationHardnessWelding and FabricationSpecifications and CodesDisclaimerAlloy Brochure

Principal Features

30 years of proven performance in “wet process” phosphoric acid

HASTELLOY® G-30® alloy (UNS N06030) is a nickel-chromium-iron material highly resistant to “wet process” phosphoric acid (P2O5). P2O5 is one of the most important industrial chemicals, being the primary source of phosphorus for agrichemical fertilizers. G-30® alloy is also moderately resistant to chloride-induced localized attack, which can be a problem beneath deposits in the evaporators used to concentrate P2O5. Furthermore, G-30® alloy is less susceptible to chloride-induced stress corrosion cracking than the stainless steels.

As a result of its high chromium content, G-30® alloy is also very resistant to other oxidizing acids, such as nitric, and mixtures containing nitric acid. It possesses moderate resistance to reducing acids, such as hydrochloric and sulfuric, as a result of its appreciable molybdenum and copper contents.

HASTELLOY® G-30® alloy is available in the form of plates, sheets, strips, billets, bars, wires, pipes, tubes, and covered electrodes. Applications include P2O5 evaporator tubes and nitric acid-based, metal pickling hardware.

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

Nominal Composition

Weight %
Nickel Balance
Chromium 30
Iron 15
Molybdenum 5.5
Tungsten 2.5
Copper 2
Niobium 0.8
Cobalt 5 max.
Manganese 1.5 max.
Silicon 0.8 max.
Carbon 0.03 max.

Resistance to "Wet Process"

Phosphoric Acid

“Wet process” phosphoric acid (P2O5) is made by reacting phosphate rock with sulfuric acid. As produced, it contains many impurities, and has a P2O5 concentration of only about 30%, because of the large amount of rinse water needed to separate it from the other main reaction product, calcium sulfate. Typical impurities include unreacted sulfuric acid, various metallic ions, fluoride ions, and chloride ions. The fluoride ions tend to form complexes with the metallic ions, and are therefore less of a problem than the chloride ions, which strongly influence electrochemical reactions between “wet process” phosphoric acid and metallic materials. Particulate matter (for example, silica particles) can also be present in “wet process” acid.

The main use of metallic materials is in the concentration process, where the “wet process” acid is taken through a series of evaporation steps, involving metallic tubing. Typically, the P2O5 concentration is raised to 54% during this process. The concentration effect upon the corrosivity of the acid is somewhat offset by the fact that the impurity levels drop as the concentration increases.

The following chart, comparing HASTELLOY® G-30® alloy with competitive stainless steels, is based on tests in three concentrations (36, 48, and 54%) of “wet process” phosphoric acid (supplied by a producer in Florida, USA) at 121°C (250°F).

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 G-30 alloy with that of other materials, it is useful to plot the 0.1 mm/y lines. In the following graphs, the lines for G-30 alloy are compared with those of 625 alloy, 254SMO alloy, and 316L stainless steel, in hydrochloric and sulfuric acids. Note that the line for G-30 alloy is slightly higher than that for 625 alloy in sulfuric acid. The hydrochloric acid concentration limit of 20% is the azeotrope, above which corrosion tests are less reliable.

 

Selected Corrosion Data

Hydrochloric Acid

Conc.Wt.% 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 <0.01 <0.01 - 0.01
1.5 - - - - - - - - -
2 - - - <0.01 <0.01 - - - 9.47
2.5 - - - <0.01 1.04 2.06 4.23 - 12.67
3 - - <0.01 <0.01 - - - - -
3.5 - - - - - - - - -
4 - - - - - - - - -
4.5 - - - - - - - - -
5 - <0.01 0.33 0.71 1.33 2.65 9.06 - -
7.5 <0.01 0.05 - - - - - - -
10 0.08 0.19 0.44 0.64 1.48 3.96 15.21 - -
15 0.13 0.31 0.66 1.87 1.47 - 11.98 - -
20 - 0.13 0.30 0.55 1.24 - 10.90 - -

Data are from Corrosion Laboratory Jobs 446-82, 168-89, and 66-96.
All tests were performed in reagent grade acids under laboratory conditions; field tests are encouraged prior to industrial use.

Sulfuric Acid

Conc.Wt.% 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 - - - - - - - - - - - -
3 - - - - - - - - - - - -
4 - - - - - - - - - - - -
5 - - - - <0.01 <0.01 - - - - - 0.47
10 - - - - <0.01 <0.01 - - - - - 0.78
20 - - - - <0.01 0.36 - - - - - 1.35
30 - - - - 0.01 0.55 - - - - - 1.53
40 - - - 0.02 0.05 0.54 - - - - - 1.95
50 - <0.01 <0.01 0.01 0.26 0.56 0.93 - - - - 3.68
60 - - <0.01 0.09 0.27 0.73 1.07 - - - - 8.46
70 - <0.01 0.01 0.11 0.36 0.98 1.38 - - - - -
80 - - 0.31 1.13 2.62 4.52 4.70 - - - - -
90 - <0.01 0.67 2.01 3.25 6.55 6.25 - - - - -
96 - - 0.45 1.86 2.04 1.86 1.52 - - - - -

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 Job 449-82.
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  - -  -  -  -  0.03
Chromic Acid 5  - -  0.02  - -  0.40
10  - -  0.14 -  -  1.23
Formic Acid 88 -  -  -  -  -  0.05
Hydrochloric Acid 1  - -  <0.01 <0.01 <0.01 0.01
2 -  <0.01 <0.01  - -  9.47
2.5 -  <0.01 1.04 2.06 4.23 - 
3 <0.01 <0.01  -  - -   -
5 0.33 0.71 1.33 2.65 -  - 
10 0.44 0.64 1.48 3.96  - - 
15 0.66 1.87 1.47 -  -  - 
20 0.30 0.55 1.24 -   -  -
Nitric Acid 50  - -  -  -  -  0.08
60  - -  -   - -  0.14
65  -  - -  -   - 0.16
Phosphoric Acid (Reagent Grade) 50 -   - -  -  <0.01 0.01
60 -  -   - -  -  0.14
70 -   -  - -  0.01 0.35
80 -  -   -  - -  0.61
85 -  -  -  -  -  0.84
Sulfuric Acid 10 - - - <0.01 <0.01 0.78
20 - - - <0.01 0.36 1.35
30 - - - 0.01 0.55 1.53
40 - - 0.02 0.05 0.54 1.95
50 <0.01 <0.01 0.01 0.26 0.56 -
60 - <0.01 0.09 0.27 0.73 -
70 <0.01 0.01 0.11 0.36 0.98 -
80 - 0.31 1.13 2.62 4.52 -
90 <0.01 0.67 2.01 3.25 6.55 -
96 - 0.45 1.86 2.04 1.86 -

Resistance to Pitting and Crevice Corrosion

Various 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 nickel 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 G-30® alloy is 55°C, and the lowest temperature at which crevice corrosion has been observed is 45°C. In Yellow Death, the corresponding temperatures are 55°C and 25°C.

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, G-30 alloy is much more resistant to this form of attack than the comparative, austenitic stainless steels.

Alloy Time to Cracking
316L 2 h
254SMO 24 h
28 36 h
31 36 h
G-30® 168 h

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. Notably, the resistance of all-weld-metal samples of G-30 alloy to key, inorganic acids is close to that of the wrought, base metal in several cases.
Chemical Concentration Temperature Corrosion Rate
wt.% F °C Weld Metal Wrought Base Metal
mpy mm/y mpy mm/y
H2SO4
 30 150 66 <0.4 <0.01 <0.4 <0.01
H2SO4
 50 150 66 0.4 0.01 0.4 0.01
H2SO4
 70 150 66 5.5 0.14 4.3 0.11
H2SO4
 90 150 66 102.4 2.60 102.8 2.61
HCl 5 100 38 <0.4 <0.01 13.0 0.33
HCl 10 100 38 27.6 0.70 17.3 0.44
HCl 15 100 38 25.2 0.64 26.0 0.66
HCl 20 100 38 20.5 0.52 11.8 0.30
HNO3
 70 Boiling 5.5 0.14 5.5 0.14

Physical Properties

Physical Property British Units Metric Units
Density RT
0.297 lb/in3
 RT
8.22 g/cm3
Electrical Resistivity RT 45.7 μohm.in RT 1.16 μohm.m
200°F 46.0 μohm.in 100°C 1.17 μohm.m
400°F 46.9 μohm.in 200°C 1.19 μohm.m
600°F 47.8 μohm.in 300°C 1.21 μohm.m
800°F 48.5 μohm.in 400°C 1.23 μohm.m
Thermal Conductivity 1000°F 49.0 μohm.in 500°C 1.24 μohm.m
- - 600°C 1.25 μohm.m
RT
69 btu.in/h.ft2.°F
 RT 10 W/m.°C
200°F
81 btu.in/h.ft2.°F
 100°C 12 W/m.°C
400°F
98 btu.in/h.ft2.°F
 200°C 14 W/m.°C
600°F
120 btu.in/h.ft2.°F
 300°C 17 W/m.°C
800°F
134 btu.in/h.ft2.°F
 400°C 19 W/m.°C
1000°F
141 btu.in/h.ft2.°F
 500°C 20 W/m.°C
Mean Coefficient of Thermal Expansion - - 600°C 21 W/m.°C
86-200°F 7.1 μin/in.°F 30-100°C 12.8 μm/m.°C
86-400°F 7.7 μin/in.°F 30-200°C 13.8 μm/m.°C
86-600°F 8.0 μin/in.°F 30-300°C 14.3 μm/m.°C
86-800°F 8.3 μin/in.°F 30-400°C 14.8 μm/m.°C
86-1000°F 8.6 μin/in.°F 30-500°C 15.3 μm/m.°C
86-1200°F 8.9 μin/in.°F 30-600°C 15.8 μm/m.°C
Dynamic Modulus of Elasticity RT
29.3 x 106psi
 RT 202 GPa
400°F
28.4 x 106psi
 200°C 196 GPa
600°F
28.2 x 106psi
 300°C 195 GPa
800°F
27.8 x 106psi
 400°C 192 GPa
1000°F
26.7 x 106psi
 500°C 187 GPa

RT= Room Temperature

Impact Strength

Test Temperature Impact Strength
°F °C ft-lbf J
RT RT 326 442
-320 -196 389 527

Impact strengths were generated using Charpy V-notch samples, machined from mill annealed plate.

Tensile Strength and Elongation

Form Thickness/ Bar Diameter Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
in mm °F °C ksi MPa ksi MPa %
Sheet 0.028 0.71 RT RT 47 324 100 689 56
Sheet 0.125 3.2 RT RT 51 352 100 689 56
Plate 0.250 6.4 RT RT 46 317 98 676 55
Plate 0.375 9.5 RT RT 45 310 100 689 65
Plate 0.500 12.7 RT RT 46 317 100 689 64
Plate 0.750 19.1 RT RT 47 324 98 676 65
Plate 1.250 31.8 RT RT 45 310 99 683 60
Bar 1.000 25.4 RT RT 46 317 100 689 60
Plate & Bar* Various 200 93 42 290 95 655 54
Plate & Bar* Various 400 204 36 248 88 607 59
Plate & Bar* Various 600 316 33 228 83 572 59
Plate & Bar* Various 800 427 31 214 80 552 60
Plate & Bar* Various 1000 538 29 200 76 524 62

*Average results from tests of 11 plate and bar products of thickness/diameter 6.4 to 31.8 mm
RT= Room Temperature

Hardness

Form Hardness, HRBW Typical ASTM Grain Size
Sheet 81 1.5 - 4
Plate 80 0 - 3
Bar 78 0 - 2

All samples tested in solution-annealed condition.
HRBW = Hardness Rockwell “B”, Tungsten Indentor.

Welding and Fabrication

HASTELLOY® G-30® 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® G-30® 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® G-30® alloy is 1177°C (2150°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® G-30® alloy, please click here.

HASTELLOY® G-30® 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 1149°C (2100°F) and the recommended finish temperature is 927°C (1700°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 of the HASTELLOY® alloys. G-30® alloy is stiffer than most austenitic stainless steels, and more energy is required during cold forming. Also, G-30® 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® G-30® 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® G-30® alloy (N06030, W86030)
Sheet, Plate & Strip SB 582/B 582P= 45
Billet, Rod & Bar SB 581/B 581B 472P= 45
Coated Electrodes SFA 5.11/ A 5.11 (ENiCrMo-11)F= 45
Bare Welding Rods & Wire SFA 5.14/ A 5.14 (ERNiCrMo-11)F= 45
Seamless Pipe & Tube SB 622/B 622P= 45
Welded Pipe & Tube SB 619/B 619SB 626/B 626P= 45
Fittings SB 366/B 366SB 462/B 462P= 45
Forgings SB 462/B 462P= 45
DIN No. 2.4603 NiCr30FeMo
TÜV -
Others NACE MR0175ISO 15156

Codes

HASTELLOY® G-30® alloy (N06030, W86030)
ASME Section l -
Section lll Class 1
Class 2
Class 3
Section Vlll Div. 1
Div. 2
Section Xll
650°F (343°C)1
B16.5
800°F (427°C)2
B16.34
800°F (427°C)3
B31.1 -
B31.3 -
VdTÜV (doc #) -

1Plate, Sheet, Bar, fittings, welded pipe/tube, seamless pipe/tube, Bolting
2Plate, Forgings, fittings
3Plate, Bar, Forgings, seamless pipe/tube

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.

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