Inconel Alloy grades at a glance with ASTM specification and equivalent chart
Inconel steel, denoting all nickel-chromium-based austenitic steels, qualifies as superalloys due to their chromium and nickel composition, exhibiting remarkable performance in high-pressure and high-temperature settings. These alloys demonstrate significant resistance to oxidation corrosion, making them suitable for applications prone to oxidation. Similar to weathering steel, Inconel materials develop an oxide layer upon initial exposure to oxidising agents, providing a protective barrier against further corrosion through oxidation. Notably, Inconel materials exhibit reduced or negligible thermally induced crystal vacancies, rendering them applicable in high-temperature environments where conventional steel or aluminium would falter. The density of Inconel varies across grades, designated by numbers like 600, 617, 625, 690, 718, and X750; for instance, Inconel 600 has a density of 8.47 grams per cubic centimetre. These grades are developed through diverse methods, including solid solution strengthening or precipitation strengthening. The formation of gamma double prime, involving cubic crystals, prevents creep at elevated temperatures, with niobium added in certain precipitation strengthening grades for this purpose. Due to rapid material hardening, cold working is impractical, and machining poses challenges, requiring specialised tools and procedures to prevent plastic deformation. The competitive pricing of Inconel makes it an attractive option, with a comprehensive price list available upon request. Different grades of the Inconel alloy find application across various industries and purposes, with Inconel X-750 commonly used in gas turbine components for blades, seals, and rotors. Predominantly utilised in the aviation, space, and gas industries, different Inconel grades serve specific functions.
Inconel Alloy Grades
Inconel 600 |
Inconel 601 |
Inconel 625 |
Inconel 718 |
Inconel X750 |
Inconel 800 |
Inconel 825 |
Inconel Alloy ASTM Standard
Products Available Shapes | International Standard |
|---|---|
Bar | ASTM B 446/ASME SB 446, ISO 9723, VdTÃœV 499, BS 3076NA21, EN 10095, DIN 17752 , ASME Code Case 1935, SAE/AMS 5666, |
Wire | DIN 17753, SAE/AMS 5837, ISO 9724 |
Sheet / Plate | ASTM B 443/ASTM SB 443,ISO 6208, VdTÃœV 499, BS 3072NA21 (Sheet, Plates), EN 10095, DIN 17750, ASME Code Case 1935, SAE/AMS 5599 & 5869 & MAM 5599, |
| Pipe / Tube | ASTM B444/ B829, ASME SB 444/ SB 829 (Seamless), ASME SB 704/SB 751 and ASTM B704/B 751 (Welded), ASME SB 705/ SB 775 and ASTM B705/B 775 (Welded), VdTÃœV 499, BS 3074NA21 (Seamless), ISO 6207, SAE/AMS 5581 (Seamless & Welded), DIN 17751, ASME Code Case 1935. |
Pipe Fittings (Buttweld) | ASTM B 366/ ASME SB 366 |
Forging/ Forged Items | ASTM B 564/ ASME SB 564, DIN 17754, ISO 9725 |
Welding Wire | A5.14 ERNiFeCr-2 |
| Heat Resisting Steels & Alloys | DIN 17744, ISO 4955A |
Inconel Alloy Temperature Range
| Inconel 600 Heat Capacity units | Metric: 0.444 J/g-°C |
| Inconel 625 Heat Capacity units | Metric: 0.41 J/g-°C English: 0.098 BTU/lb-°F |
Inconel Alloy Applications
- Aerospace industries
- Marine applications
- Sea-water applications
- Jet Engine Components
- Commercial Gas Turbines
- Food Processing
- Chemical Processing
- Cryogenic Storage Tanks
- Power generation
- Nuclear reactors
- Gas turbines
- Pressure vessels
Inconel Alloy Composition
| Inconel | Element, proportion by mass (%) | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ni | Cr | Fe | Mo | Nb & Ta | C | Co | Cu | Mn | Al | Ti | Si | S | P | B | |
| 600 | ≥72.0 | 14.0–17.0 | 6.0–10.0 | – | – | ≤0.15 | N/A | ≤0.5 | ≤1.0 | – | – | ≤0.5 | ≤0.015 | – | – |
| 617 | 44.2–61.0 | 20.0–24.0 | ≤3.0 | 8.0–10.0 | – | 0.05–0.15 | 10.0–15.0 | ≤0.5 | ≤0.5 | 0.8–1.5 | ≤0.6 | ≤0.5 | ≤0.015 | ≤0.015 | ≤0.006 |
| 625 | ≥58.0 | 20.0–23.0 | ≤5.0 | 8.0–10.0 | 3.15–4.15 | ≤0.1 | ≤1.0 | – | ≤0.5 | ≤0.4 | ≤0.4 | ≤0.5 | ≤0.015 | ≤0.015 | – |
| 690 | ≥58 | 27–31 | 7–11 | – | – | ≤0.05 | – | ≤0.50 | ≤0.50 | – | – | ≤0.50 | ≤0.015 | – | – |
| Nuclear grade 690 | ≥58 | 28–31 | 7–11 | – | – | ≤0.04 | ≤0.10 | ≤0.50 | ≤0.50 | – | – | ≤0.50 | ≤0.015 | – | – |
| 718 | 50.0–55.0 | 17.0–21.0 | Remainder | 2.8–3.3 | 4.75–5.5 | ≤0.08 | ≤1.0 | ≤0.3 | ≤0.35 | 0.2–0.8 | 0.65–1.15 | ≤0.35 | ≤0.015 | ≤0.015 | ≤0.006 |
| X-750 | ≥70.0 | 14.0–17.0 | 5.0–9.0 | – | 0.7–1.2 | ≤0.08 | ≤1.0 | ≤0.5 | ≤1.0 | 0.4–1.0 | 2.25–2.75 | ≤0.5 | ≤0.01 | – | – |
Inconel Alloy Properties
| Products | Hardness, Rockwell | Form and Condition | Yield Strength | Tensile Strength | Elongation % | ||
|---|---|---|---|---|---|---|---|
| ksi | MPa | ksi | MPa | ||||
| Bars | 65-85B | Cold drawn Annealed | 25-50 | 170-345 | 80-100 | 550-690 | 55-35 |
| Plates | 65-85B | Hot rolled Annealed | 30-50 | 205-345 | 80-100 | 550-725 | 55-35 |
| Sheets | 88B max | Cold Rolled (CR) Annealed | 30-45 | 205-310 | 80-100 | 550-690 | 55-35 |
| Pipe/ Tubes | 88B max | Cold Drawn Annealed | 25-50 | 170-345 | 80-100 | 550-690 | 55-35 |
| Wires | – | Cold Drawn Annealed | 35-75 | 240-520 | 80-120 | 550-830 | 45-20 |
| Wires | – | Cold Drawn No 1 Temper | 70-105 | 480-725 | 105-135 | 725-930 | 35-15 |
| Wires | – | Spring Temper | 150-210 | 1035-1450 | 170-220 | 1170-1520 | 5-2 |
| Bars/ Rods | ≤ 287 HB | Annealed | 60 | 414 | 120 | 827 | 30 |
| Sheet | 145-240 | Annealed | 60 | 414 | 120 | 827 | 30 |
| Tube | – | Annealed | 60 | 414 | 120 | 827 | 35 |
Inconel Alloy Melting Point
Inconel has a higher melting point of 2,540°F-2,600°F (1,390°C-1,425°C), check below the grade wise melting range.
Inconel 718 Melting Point Range | Solution Treated: 2500-2600 Deg F Solution Treated and Aged: 1370-1430 Deg C |
Inconel 601 Melting Point Range | 1411 Deg C (2571 Deg F) |
Inconel 600 Melting Point Range | Metric: 1354 – 1413 Deg C English: 2470 – 2580 Deg F |
Inconel 625 Melting Point Range | 2350 – 2460 Deg F (1280 – 1350 Deg C) |