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Inconel 617 Round Bars

INCONEL Alloy 600, Alloy 601, Alloy 617, Alloy 625, Alloy 718

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INCONEL ALLOY is renowned for its exceptional performance in extreme environments, particularly where high temperatures and corrosive conditions prevail. These nickel-chromium-based superalloys maintain their strength and resist oxidation and corrosion across a wide temperature range, making them indispensable in industries such as oil and gas, aerospace, chemical processing, and marine engineering.​

Inconel 600/UNS N06600

Inconel 600 is a solid-solution strengthened alloy primarily composed of nickel and chromium. It offers outstanding resistance to oxidation and corrosion, making it suitable for chemical processing, aerospace, and nuclear engineering applications. The alloy’s versatility allows it to withstand various corrosive environments and high-temperature conditions.​

Inconel 601/UNS N06601

Building upon the foundation of Inconel 600, Inconel 601 enhances oxidation resistance with the addition of aluminum. This modification forms a protective oxide layer, enabling the alloy to perform exceptionally well in high-temperature environments. Common applications include thermal processing equipment, heat-treating baskets, and components in pollution control systems.

Inconel 617/UNS N06617

Inconel 617 combines nickel, chromium, cobalt, and molybdenum to deliver a superior strength and oxidation resistance balance at elevated temperatures. Its high-temperature strength and corrosion resistance make it ideal for gas turbines, petrochemical processing, and heat exchangers.​

Inconel 625/UNS N06625

Noted for its remarkable fatigue and thermal-fatigue strength, Inconel 625 is highly resistant to oxidation and corrosion. This alloy is widely used in aerospace, marine, and chemical processing industries, particularly in applications requiring high strength and resistance to aggressive environments.​

Inconel 718/UNS N07718

Inconel 718 is a precipitation-hardenable nickel-chromium alloy containing significant amounts of iron, niobium, and molybdenum, along with lesser amounts of aluminum and titanium. It combines corrosion resistance and high strength with outstanding weldability, including resistance to post-weld cracking. The alloy has excellent creep-rupture strength at temperatures up to 1300°F (700°C), making it suitable for gas turbines, rocket motors, and nuclear reactors.

Inconel 600 Plate
Inconel 600 Plate
Inconel 600 Seamless Tubes
Inconel 600 Seamless Tubes
Inconel 625 Seamless Tubes
Inconel 625 Seamless Tubes
Inconel 718 Round Bars
Inconel 718 Round Bars
Inconel 617 Round Bars
Inconel 617 Round Bars

Chemical Composition (wt%) of Inconel Alloy

Alloy Ni Cr Fe Mo Co Nb Al Ti Mn Si C Other
Inconel 600 ≥72 14-17 6-10 – – – – – ≤1 ≤0.5 ≤0.15 Cu ≤0.5, S ≤0.015
Inconel 601 58-63 21-25 Balance – – – 1.0-1.7 – ≤1 ≤0.5 ≤0.10 S ≤0.015
Inconel 617 ≥44.5 20-24 ≤3 8-10 10-15 – 0.8-1.5 – ≤0.5 ≤0.5 0.05-0.15 B ≤0.006, S ≤0.015
Inconel 625 ≥58 20-23 ≤5 8-10 ≤1 3.15-4.15 ≤0.4 ≤0.4 ≤0.5 ≤0.5 ≤0.10 P ≤0.015
Inconel 718 50-55 17-21 Balance 2.8-3.3 ≤1 4.75-5.5 0.2-0.8 0.65-1.15 ≤0.35 ≤0.35 ≤0.08 B ≤0.006, Cu ≤0.3

Mechanical Properties (Annealed Condition) of Inconel Alloy

Alloy Tensile Strength (MPa) Yield Strength (MPa) Elongation (%) Hardness (Rockwell)
Inconel 600 550 (80 ksi) 240 (35 ksi) 30% B80
Inconel 601 550 (80 ksi) 205 (30 ksi) 30% B88
Inconel 617 750 (109 ksi) 345 (50 ksi) 35% B95
Inconel 625 760 (110 ksi) 345 (50 ksi) 30% B95
Inconel 718 1240 (180 ksi) 1035 (150 ksi) 12% C35

Product Forms and ASTM Standards

Alloy Pipes & Tubes Plates, Sheets & Strips Bars & Rods Forgings Rings
Inconel 600 ASTM B167 ASTM B168 ASTM B166 ASTM B564 Custom
Inconel 601 ASTM B167 ASTM B168 ASTM B166 ASTM B564 Custom
Inconel 617 ASTM B166 ASTM B168 ASTM B166 ASTM B564 Custom
Inconel 625 ASTM B444, B705 ASTM B443 ASTM B446 ASTM B564 Custom
Inconel 718 ASTM B983 ASTM B670 ASTM B637 ASTM B637 AMS 5662

Heat Treatment Process of Inconel Alloy

Alloy Solution Annealing Temperature Cooling Method Precipitation Hardening (if applicable)
Inconel 600 1010–1150°C (1850–2100°F) Air cool Not applicable
Inconel 601 1065–1180°C (1950–2150°F) Air cool Not applicable
Inconel 617 1120–1205°C (2050–2200°F) Air cool Not applicable
Inconel 625 980–1040°C (1800–1900°F) Water quench Not applicable
Inconel 718 980°C (1800°F) for 1 hr, then 720°C (1325°F) for 8 hrs Air cool Yes — age-hardened for high-strength

Weldability of Inconel Alloy

Alloy Weldability Rating Recommended Welding Process Post-Weld Heat Treatment
Inconel 600 Excellent GTAW (TIG), GMAW (MIG), SMAW (Stick) Not required
Inconel 601 Good GTAW, GMAW, SMAW Not required
Inconel 617 Good GTAW, GMAW Not required
Inconel 625 Excellent GTAW, GMAW, SMAW, PAW (Plasma) Not required
Inconel 718 Moderate (susceptible to cracking) GTAW, Electron Beam, Laser Solution annealing is recommended after welding

Welding Note:
Inconel 625 and 718 show excellent weldability with minimal cracking.
Inconel 718 requires precise heat control to avoid micro-cracks due to its precipitation-hardened structure.

Corrosion Resistance Comparison

Alloy Oxidation Resistance Sulfidation Resistance Acid Resistance Seawater Resistance
Inconel 600 Excellent up to 1095°C (2000°F) Moderate Good (Nitric, Hydrochloric acids) Moderate
Inconel 601 Outstanding up to 1250°C (2280°F) Excellent Limited (resists some acids) Limited
Inconel 617 Outstanding up to 1100°C (2000°F) Excellent Moderate Limited
Inconel 625 Excellent up to 980°C (1800°F) Good Excellent (resists most acids) Excellent
Inconel 718 Good up to 650°C (1200°F) Good Good Moderate

Corrosion Resistance Highlights:
Inconel 625 excels in marine environments due to its molybdenum content, making it highly resistant to pitting and crevice corrosion.
Inconel 601 forms a tightly adherent oxide scale, making it ideal for high-temperature oxidation.
Inconel 718 trades some corrosion resistance for strength and creep resistance, especially in high-stress aerospace applications.
Industry-Specific Applications

Alloy Aerospace Oil & Gas Chemical Processing Marine & Offshore Power Generation
Inconel 600 Jet engine components, exhaust liners Furnace components, heat exchangers Caustic alkali environments Not ideal (limited seawater resistance) Steam superheaters, nuclear reactor components
Inconel 601 Afterburners, combustion cans Reformer tubes, flare stacks High-temp sulfur-bearing atmospheres Not ideal Gas turbines, heat treating equipment
Inconel 617 Gas turbines, combustion liners High-temp piping, flue gas systems High-temperature chemical processing Limited use Heat exchangers, petrochemical plants
Inconel 625 Rocket engine thrust chambers, heat shields Sour gas pipelines, offshore platforms Acid-resistant piping, scrubbers Propeller blades, seawater components Nuclear reactors, waste heat boilers
Inconel 718 Turbine discs, jet engines, space shuttle components Downhole tools, casing hangers Acidic environments needing high-strength Limited use Gas turbines, cryogenic tanks

Key Takeaways:
Inconel 625 shines in marine and chemical environments due to superior corrosion resistance.
Inconel 718 rules aerospace thanks to high strength and creep resistance — but is overkill for corrosion-heavy environments.
Inconel 601 is unbeatable for extreme heat environments like furnaces and gas turbines.

Cost Analysis

Alloy Raw Material Cost Machinability Welding Cost Lifecycle Value
Inconel 600 $$ (Moderate) Fair (work hardens) Moderate High (long lifespan in heat/corrosion environments)
Inconel 601 $$ (Moderate) Fair (better than 600) Moderate Very High (superior oxidation resistance)
Inconel 617 $$$ (High) Difficult (high cobalt content) High (special handling) High (high-temp, long-life applications)
Inconel 625 $$$ (High) Difficult (gummy behavior) Low (excellent weldability) Excellent (seawater, acidic environments)
Inconel 718 $$$$ (Very high) Difficult (age-hardened) High (crack-sensitive) Excellent (aerospace, high-stress parts)

Cost Tips:

Inconel 625 offers the best cost-to-performance ratio for corrosion-heavy environments.
Inconel 718 is costly but justified where strength and high-temp creep resistance are critical — especially in aerospace.
Inconel 601 wins for high-temperature applications thanks to its balance of cost, oxidation resistance, and machinability.

Material Selection Guidance (By Industry)

Aerospace

Inconel 718: Best for jet engines, turbine blades, and rocket motors due to high strength and creep resistance.
Inconel 625: Great for heat shields and exhaust ducts — corrosion-resistant and handles extreme temps.
Recommendation: Use 718 for load-bearing components and 625 for parts exposed to corrosive exhaust gases.

Oil & Gas

Inconel 625: Perfect for sour gas environments, offshore platforms, and heat exchangers — fights pitting, crevice corrosion, and chloride stress corrosion cracking.
Inconel 617: Great for flue gas systems and reformers — withstands high-temp gas exposure.
Recommendation: 625 for corrosion-critical parts, 617 for high-temp exposure.

Chemical Processing

Inconel 600: Handles caustic environments and alkaline conditions, ideal for heat exchangers and piping.
Inconel 625: Superior acid resistance — perfect for scrubbers, ducting, and reactors.
Recommendation: 600 for basic corrosion resistance, 625 for aggressive acids and seawater conditions.

Marine & Offshore

Inconel 625: Best choice for propellers, marine exhausts, and seawater piping — outstanding resistance to saltwater corrosion.
Recommendation: 625 all the way — few alloys can match its marine corrosion performance.

Power Generation

Inconel 601: Excellent for gas turbines, superheater tubing, heat-treating equipment — high temp, oxidation, and carburization resistance.
Inconel 625: Great for nuclear reactors, waste heat boilers, and steam superheaters.
Inconel 718: Ideal for gas turbines under high mechanical loads.
Recommendation: 601 for heat environments, 625 or 718 where strength and corrosion resistance are key.

What is the Best Alloy for the Job?

Need Best Alloy Choice
High-temperature oxidation resistance Inconel 601
Sour gas, marine, or chemical corrosion Inconel 625
High strength + high temp creep resistance Inconel 718
Heat exchangers and caustic alkali handling Inconel 600
High-temp gas and petrochemical environments Inconel 617

Conclusion

Selecting the appropriate Inconel alloy depends on specific application requirements, including environmental conditions, mechanical stresses, and temperature ranges. Understanding the unique properties of each alloy enables engineers and material specialists to make informed decisions, ensuring reliability and longevity in critical components. For comprehensive technical data and guidance, consulting resources provided by Golden Sunbird Metals are highly recommended. Don’t hesitate to get in touch with us at [email protected].

Inconel 617 vs. Inconel 718

Inconel 617 vs. Inconel 718: A Detailed Comparison for High-Temperature Applications

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Introduction

Engineers widely recognize Inconel alloys’ ability to perform in extreme conditions, particularly in high-temperature and corrosive environments. Among the numerous variants, Inconel 617 and Inconel 718 are two popular choices, each offering unique properties tailored to specific industrial applications. In this post, Inconel 617 vs. Inconel 718, we’ll explore the key differences, properties, and applications of Inconel 617 and Inconel 718 to help you make an informed decision for your project.

Introduction to Inconel Alloys

Engineers design Inconel alloys, primarily composed of nickel and chromium, to withstand severe conditions, including high temperatures, corrosion, and oxidation. Industries such as aerospace, power generation, and chemical processing widely use these alloys. While both Inconel 617 and Inconel 718 are part of the Inconel family, they serve different roles due to their distinct compositions and properties.

Inconel 617: Composition, Properties, and Applications

Chemical Composition:

  • Nickel (Ni): 44.5-55.0%
  • Chromium (Cr): 20.0-24.0%
  • Cobalt (Co): 10.0-15.0%
  • Molybdenum (Mo): 8.0-10.0%
  • Aluminum (Al): 0.8-1.5%
  • Carbon (C): 0.05-0.15%
  • Iron (Fe): 3.0% maximum

Key Properties:

  • High-Temperature Strength:  Inconel 617 is engineered to maintain its strength at temperatures up to 1100°C (2000°F), which makes it ideal for high-temperature applications.
  • Oxidation and Corrosion Resistance: The alloy offers excellent resistance to oxidation and carburization at elevated temperatures and good corrosion resistance in a wide range of environments.
  • Fabricability: Inconel 617 is known for its good fabricability, allowing manufacturers to weld and form it into complex shapes without losing strength.

Applications:

  • Gas Turbines: Inconel 617 is commonly used in gas turbine components such as combustion cans, ducting, and transition liners, where it withstands high temperatures and corrosive gases.
  • Nuclear Reactors: The alloy’s high-temperature strength and resistance to radiation make it suitable for atomic reactor components.
  • Chemical Processing: Inconel 617 is also used in chemical processing, particularly in high-temperature gases and corrosive environments.

Inconel 718: Composition, Properties, and Applications

Chemical Composition:

  • Nickel (Ni): 50.0-55.0%
  • Chromium (Cr): 17.0-21.0%
  • Iron (Fe): Balance (remains the predominant element)
  • Molybdenum (Mo): 2.8-3.3%
  • Columbium + Tantalum (Cb+Ta): 4.75-5.5%
  • Titanium (Ti): 0.65-1.15%
  • Aluminum (Al): 0.2-0.8%
  • Carbon (C): 0.08% maximum

Key Properties:

  • High-Temperature Strength: Inconel 718 retains its mechanical strength up to around 700°C (1300°F) and demonstrates excellent tensile, creep, and rupture strength at elevated temperatures.
  • Corrosion Resistance: Inconel 718 offers exceptional resistance to oxidation, pitting, crevice corrosion, and stress-corrosion cracking, particularly in chloride and sulfide environments.
  • Age-Hardenable: One of Inconel 718’s key features is its ability to undergo age hardening, which enhances its strength through heat treatment.

Applications:

  • Aerospace: Engineers extensively use Inconel 718 in aerospace applications, including gas turbine engine components, rocket motors, and spacecraft parts, due to its high strength and corrosion resistance.
  • Oil and Gas:  The oil and gas industry widely uses the alloy for downhole equipment and wellhead components that face corrosive environments and high pressures.
  • Power Generation: Manufacturers employ Inconel 718 in power generation equipment, particularly in steam turbines and nuclear reactors, where its high strength and corrosion resistance are critical.
Inconel 617 vs. Inconel 718

Inconel 617 vs. Inconel 718

Key Differences: Inconel 617 vs. Inconel 718

  1. Temperature Capability: Inconel 617 can withstand higher temperatures (up to 1100°C) than Inconel 718, which is more suitable for applications up to around 700°C. This characteristic makes Inconel 617 a better choice for highly high-temperature environments, while engineers prefer Inconel 718 for applications requiring high strength at moderately high temperatures.
  2. Mechanical Strength: Due to its age-hardenable nature, Inconel 718 offers superior mechanical strength at lower temperatures, making it ideal for aerospace and other high-stress applications. In contrast, although Inconel 617 is strong, it does not provide the same level of strength as Inconel 718; however, it excels in environments that require extreme temperature resistance.
  3. Corrosion Resistance: Both alloys offer excellent corrosion resistance, but Inconel 718 has a slight edge in environments with chloride and sulfide exposure, making it more suitable for oil and gas applications. Inconel 617 is better suited for high-temperature environments that require critical oxidation and carburization resistance.
  4. Fabricability:  Inconel 617 is known for its good fabricability, allowing manufacturers to weld and form it more easily. Inconel 718, while also weldable, requires careful control of heat treatment processes to achieve optimal mechanical properties.

Inconel 617 vs. Inconel 718: Choosing the Right Alloy for Your Application

When selecting between Inconel 617 and Inconel 718, consider the following factors:

  • Temperature Requirements: Inconel 617 may be the better choice if your application involves extremely high temperatures. For applications requiring high strength at moderately high temperatures, Inconel 718 is likely more suitable.
  • Corrosion Resistance: Inconel 718’s corrosion resistance may be preferable in environments with high levels of chloride or sulfide. When seeking high-temperature oxidation resistance, consider Inconel 617.
  • Mechanical Strength: If mechanical strength is a primary concern, especially in aerospace or other high-stress environments, Inconel 718 is likely the better option due to its age-hardenable properties.
  • Fabrication Needs: If ease of fabrication is essential, Inconel 617 may offer more flexibility in welding and forming.

Conclusion

Both Inconel 617 and Inconel 718 are exceptional materials, each designed for specific conditions and applications. Understanding the differences between these alloys will help you select the suitable material for your project, ensuring optimal performance and longevity.

Whether you are working in aerospace, chemical processing, power generation, or another high-temperature industry, the choice between Inconel 617 and Inconel 718 should be based on carefully assessing your application’s requirements. Consult with materials experts if you need further guidance in selecting a suitable alloy.