Table of Contents
Introduction
Inconel 617 is a high-performance nickel-chromium-cobalt-molybdenum alloy prized for its exceptional strength, oxidation resistance, and corrosion resistance at elevated temperatures, maintaining stability up to 2100°F (1150°C). This article provides an in-depth look into 617 Inconel covering its chemical composition, properties, specifications, and industry applications, offering a comprehensive guide on the advantages of using Alloy 617 in extreme environments.
What is Inconel 617?
Inconel 617 (UNS N06617) is a versatile alloy designed to perform in high-temperature, corrosive environments. Its unique composition allows it to form a stable oxide layer that withstands spalling, making it ideal for applications with severe thermal cycling. Known for its high mechanical strength and excellent resistance to oxidation, this alloy is commonly used in industries like gas turbines, petrochemical processing, nuclear energy, and thermal processing equipment.
What Are the Specifications of Inconel Alloy 617?
617 Inconel Equivalent
| Specification | Equivalent |
| UNS | N06617 |
| AMS | 5887 |
| ASTM | B166, B168, B751 |
| DIN | W.Nr. 2.4663 |
| EN | 2.4663 |
| JIS | NCF 617 |
Inconel 617 ASTM Standard
| Shape | ASTM Standard |
| Bars, Wire | ASTM B166 |
| Plates, Sheets | ASTM B168 |
| Pipes, Tubes | ASTM B751 |
Inconel 617 Chemical Composition
| Element | Composition (%) |
| Nickel (Ni) | Balance |
| Chromium (Cr) | 20.0 – 24.0 |
| Cobalt (Co) | 10.0 – 15.0 |
| Molybdenum (Mo) | 8.0 – 10.0 |
| Iron (Fe) | Max 3.0 |
| Aluminum (Al) | 0.8 – 1.5 |
| Carbon (C) | Max 0.05 |
| Manganese (Mn) | Max 1.0 |
| Silicon (Si) | Max 0.5 |
Inconel Metal 617 Mechanical Properties
| Property | Value |
| Tensile Strength | 100 ksi (min) |
| Yield Strength | 50 ksi (min) |
| Elongation | 35% (min) |
| Hardness (Rockwell B) | 95 HRB |
Inconel Metal 617 Physical Properties
| Property | Value |
| Density | 8.36 g/cm³ |
| Melting Point | 1330-1380°C |
| Thermal Conductivity | 11.2 W/m·K (at 20°C) |
| Specific Heat | 0.102 cal/g°C |
Nickel Alloy 617 Corrosion Resistance
| Environment | Corrosion Resistance Performance |
| Oxidizing Atmospheres | Excellent resistance up to 2100°F (1150°C) |
| Sulfur-bearing Environments | Moderate resistance up to 1700°F (927°C) |
| Aqueous Environments | Moderate resistance in mild aqueous solutions |
| Carburizing Atmospheres | Good resistance to carburization up to 1800°F (982°C) |
617 Inconel Heat Treatment
| Heat Treatment Process | Temperature Range |
| Annealing | 1800°F – 2150°F (982°C – 1177°C) |
| Solution Treatment | 2100°F – 2150°F (1149°C – 1177°C) |
What Are the Benefits of Inconel Alloy 617?
- High Oxidation Resistance: Withstands oxidation up to 2100°F, forming a stable protective oxide layer.
- High-Temperature Strength: Retains mechanical strength in extreme heat, ideal for demanding industrial applications.
- Corrosion Resistance: Resists various forms of corrosion, including carburization and sulfur-bearing environments.
- Ease of Fabrication: Readily formed, machined, and welded, adding versatility to its high-performance properties.
What is Inconel 617 Used For?
- Gas Turbines: Ideal for turbine blades and combustors that face high temperatures.
- Petrochemical Processing: Suitable for reactors and equipment exposed to high-temperature, corrosive atmospheres.
- Nuclear Power Systems: Used in heat exchangers and reactor components for stability under radiation and heat.
- Thermal Processing Equipment: Perfect for furnace parts and heat-treating components in demanding environments.
How Does Inconel Alloy 617 Compare to Other Alloys?
Inconel 617 vs 625
Inconel 617 and Inconel 625 both provide high-temperature strength and corrosion resistance. 617 Inconel, with higher chromium and cobalt, excels in oxidation resistance up to 2100°F (1150°C), making it ideal for gas turbines and petrochemical reactors. In contrast, Inconel 625’s molybdenum and niobium improve pitting and crevice corrosion resistance, making it more suitable for marine environments.
Inconel 617 vs. Hastelloy X
Inconel 617 and Hastelloy X are both high-temperature alloys, but Alloy 617 offers superior oxidation resistance due to its higher chromium. This makes it preferred for cyclic heating applications in gas turbines. Hastelloy X, though strong at high temperatures, is often used in applications like aircraft components where fabrication ease is prioritized.
Conclusion
Inconel 617’s combination of high-temperature strength, oxidation resistance, and corrosion resistance makes it invaluable in industries like gas turbines, petrochemical processing, and nuclear power. Its durability and versatility under extreme conditions make it an excellent choice for applications that demand reliable performance.
For more information on high-performance alloys like 617 Inconel, contact us today to see how it can benefit your next project.
FAQs
Is Inconel 617 resistant to carburization?
Yes, Inconel 617 exhibits good resistance to carburization, making it suitable for environments where exposure to carbon-rich gases occurs at high temperatures.
What is the difference between Inconel 601 and 617?
Inconel 601 is a nickel-chromium-iron alloy with high oxidation resistance up to 2200°F, ideal for thermal processing. 617 Inconel, with added cobalt and molybdenum, provides enhanced strength and oxidation resistance up to 2100°F, making it better suited for extreme applications like gas turbines and nuclear reactors.
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