Table of Contents
Introduction
Inconel 601 is a high-performance nickel-chromium-iron alloy prized for its outstanding oxidation and corrosion resistance. Its unique composition creates a stable oxide layer, making it ideal for challenging environments with intense thermal cycling. This article delves into 601 Inconel’s chemical makeup, key properties, and applications across industries like thermal processing and power generation, providing a comprehensive guide to its benefits and uses.
What is Inconel 601?
Inconel 601 (UNS N06601) is a nickel-chromium-iron alloy renowned for excellent oxidation and corrosion resistance at temperatures up to 2200°F. It forms a durable oxide layer that resists spalling during severe thermal cycling, maintaining high strength and ductility over extended use. Common in thermal and chemical processing, pollution control, aerospace, and power generation, 601 Inconel excels in oxidizing environments but is not recommended for sulfur-bearing, reducing atmospheres. With high chromium and added aluminum, it offers reliable oxidation resistance, good mechanical strength, and is readily formed, machined, and welded.
What Are the Specifications of Inconel Alloy 601?
601 Inconel Equivalent
| Specification | Equivalent |
| UNS | N06601 |
| AMS | 5715, 5716 |
| ASTM | B166, B167, B168 |
| DIN | W.Nr. 2.4851 |
| EN | 2.4851 |
| JIS | NCF 601 |
| GB (China) | GH3608 |
Inconel 601 ASTM Standard
| Shape | ASTM Standard |
| Bars | ASTM B166 |
| Plates, Sheets | ASTM B168 |
| Pipes, Tubes | ASTM B167, B751 |
Inconel 601 Chemical Composition
| Element | Composition (%) |
| Nickel (Ni) | 58.0 – 63.0 |
| Chromium (Cr) | 21.0 – 25.0 |
| Iron (Fe) | Balance |
| Aluminum (Al) | 1.0 – 1.7 |
| Carbon (C) | Max 0.10 |
| Manganese (Mn) | Max 1.0 |
| Silicon (Si) | Max 0.5 |
| Sulfur (S) | Max 0.015 |
| Copper (Cu) | Max 1.0 |
Inconel Metal 601 Mechanical Properties
| Property | Value |
| Tensile Strength | 80 ksi (min) |
| Yield Strength | 30 ksi (min) |
| Elongation | 30% (min) |
| Hardness (Rockwell B) | 95 HRB |
Inconel Metal 601 Physical Properties
| Property | Value |
| Density | 8.11 g/cm³ |
| Melting Point | 1360-1411°C |
| Thermal Conductivity | 12.5 W/m·K (at 20°C) |
| Specific Heat | 0.1 cal/g°C |
Nickel Alloy 601 Corrosion Resistance
| Environment | Corrosion Resistance Performance |
| Oxidizing Atmospheres | Excellent resistance up to 2200°F (1204°C) |
| Reducing Atmospheres | Not recommended; limited resistance |
| Sulfur-bearing Atmospheres | Moderate resistance up to 1600°F (870°C) |
| Aqueous Environments | Good resistance in mild aqueous solutions |
| Carburizing Atmospheres | Good resistance to carburization at elevated temperatures |
Inconel 601 Heat Treatment
| Heat Treatment Process | Temperature Range |
| Annealing | 1800°F – 2100°F (982°C – 1149°C) |
| Solution Annealing | 2100°F – 2200°F (1149°C – 1204°C) |
| Stabilizing | 1200°F – 1600°F (649°C – 871°C) |
What Are the Benefits of Inconel Alloy 601?
- Outstanding Oxidation Resistance: Withstands oxidation up to 2200°F (1204°C), forming a protective oxide layer even under thermal cycling.
- High-Temperature Strength: Retains strength and stability in extreme heat, ideal for industrial furnaces and heat-treating.
- Corrosion Resistance: Resists aqueous corrosion, oxidation, and carburization, especially in oxidizing environments.
- Metallurgical Stability: Maintains durability with a stable face-centered-cubic structure.
- Ease of Fabrication: Easily formed, machined, and welded, including compatibility with GTAW welding.
- Moderate Sulfidation Resistance: Offers limited protection in sulfur-bearing environments at high temperatures.
What is Inconel 601 Used For?
- Industrial Furnaces: Furnace muffles, radiant tubes, retorts
- Heat-Treating Equipment: Trays, fixtures, baskets
- Chemical Processing: Catalytic recovery systems, processing reactors
- Pollution Control Systems: Waste treatment incinerators, flare stacks
- Gas Turbines: Combustion chambers, turbine seals
- Power Generation Equipment: Boiler components, heat exchanger tubing
- Thermal Processing Applications: Kilns, annealing equipment
- Aerospace Components: Jet engine exhaust systems, afterburners
- Metal and Glass Making Industries: Thermowell sheathing, oxygen injection tubes
How Does Inconel 601 Compare to Other Alloys?
Inconel 601 vs 600
Inconel 601 and Inconel 600 are nickel-chromium alloys with strong oxidation and corrosion resistance. However, Alloy 601 has an edge in high-temperature oxidation due to its added aluminum, forming a stable oxide layer that withstands cyclic heating. While both alloys are suitable for heat-treating and chemical processing, 601 Inconel’s enhanced oxidation stability makes it ideal for cyclic thermal applications.
Inconel 601 vs 625
Inconel 601 and Inconel 625 offer durability and corrosion resistance, but each alloy is optimized for different environments. Inconel 625, with higher molybdenum and niobium, is more suited to marine and severe aqueous corrosion. In contrast, 601 Inconel excels in high-temperature oxidizing atmospheres, making it preferred for thermal processing, pollution control, and power generation applications.
Conclusion
Inconel 601 is a top-performing high-temperature alloy, valued for its oxidation resistance, durability, and stability in corrosive environments. Ideal for thermal processing, chemical manufacturing, and power generation. Its unique composition ensures reliability in demanding applications. Contact us today to learn how Nickle Alloy 601 can enhance your project with its exceptional strength and resistance.
FAQs
How to weld Inconel 601?
Inconel 601 can be welded using standard welding methods such as Gas Tungsten Arc Welding (GTAW) with matching Inconel 601 filler wire. For improved strength and oxidation resistance, RA 602 CA fillers can also be used. Pre-heating is not typically required, but controlled heat input and interpass temperature are recommended to prevent cracking.
What is the max temperature for Inconel 601?
The maximum service temperature for Inconel 601 is approximately 2200°F (1204°C), where it maintains excellent oxidation and corrosion resistance, making it suitable for high-temperature applications like industrial furnaces and heat-treating equipment.
Is Inconel 601 suitable for marine environments?
While Inconel Alloy 601 offers good corrosion resistance, it is not specifically designed for marine environments. For applications involving seawater or marine atmospheres, alloys like Inconel 625, which have higher resistance to pitting and crevice corrosion, are more suitable.
Read More:
What is Inconel 600 (UNS N06600)?