Hastelloy C276 (UNS N10276) Alloy – A Complete Guide

In industries where equipment is exposed to aggressive chemicals, high temperatures, and harsh environments, the choice of material is critical to safety and performance. One of the most trusted materials for such applications is Hastelloy C276 (UNS N10276), a nickel-molybdenum-chromium alloy with outstanding resistance to corrosion and oxidizing agents. Known for its ability to withstand some of the most severe conditions, Hastelloy C276 has become a preferred material in chemical processing, pollution control, marine engineering, and many other industries.

This complete guide will cover the composition, properties, advantages, and applications of Hastelloy C276, along with its role in modern engineering.

What is Hastelloy C276?

Hastelloy C276 is a superalloy primarily made of nickel, with significant amounts of molybdenum and chromium. It is designed to resist strong oxidizers, reducing agents, and mixed industrial chemicals. This alloy is also known as UNS N10276 and is covered under standards such as ASTM B575, B574, B622, and B619.

Its excellent versatility and proven track record have made Hastelloy C276 a go-to solution for severe service environments where other alloys, including stainless steels, may fail.

Chemical Composition of Hastelloy C276

The typical chemical composition of Hastelloy C276 is as follows:

  • Nickel (Ni): Balance

  • Molybdenum (Mo): 15 – 17%

  • Chromium (Cr): 14.5 – 16.5%

  • Iron (Fe): 4 – 7%

  • Tungsten (W): 3 – 4.5%

  • Cobalt (Co): ≤ 2.5%

  • Manganese (Mn): ≤ 1%

  • Vanadium (V): ≤ 0.35%

  • Silicon (Si): ≤ 0.08%

  • Carbon (C): ≤ 0.01%

This carefully balanced composition provides excellent resistance to oxidizing and reducing agents, making it highly adaptable for different environments.

Mechanical Properties

Hastelloy C276 demonstrates excellent mechanical strength and toughness even at high temperatures.

  • Tensile Strength: Approx. 690 MPa

  • Yield Strength: Approx. 283 MPa

  • Elongation: 40% minimum

  • Hardness: Around 95 HRB

  • Density: 8.89 g/cm³

These mechanical properties allow Hastelloy C276 to perform reliably under stress, pressure, and fluctuating conditions.

Key Characteristics of Hastelloy C276

  1. Outstanding Corrosion Resistance – Resists oxidizing and reducing environments, including chlorine, ferric, and cupric chlorides.

  2. Low Carbon Content – Prevents carbide precipitation during welding, reducing susceptibility to grain boundary corrosion.

  3. Resistance to Pitting and Crevice Corrosion – Particularly important in chemical and marine environments.

  4. Versatility – Can be used in both oxidizing and reducing conditions.

  5. Fabricability – Easily formed, welded, and machined without losing strength.

  6. Temperature Resistance – Performs well in environments up to 1040°C.

Advantages of Using Hastelloy C276

  • Durability: Long service life reduces replacement costs.

  • Safety: Prevents leakage or equipment failure in aggressive chemical environments.

  • Versatility: Suitable for a wide range of industries.

  • Reliability: Trusted in critical applications like pollution control and chemical reactors.

  • Low Maintenance: Reduced need for frequent inspections and repairs.

Applications of Hastelloy C276

Chemical Processing

Hastelloy C276 is widely used in reactors, heat exchangers, and evaporators that handle aggressive chemicals such as hydrochloric acid, sulfuric acid, and chlorine gas.

Pollution Control Equipment

Flue gas desulfurization (FGD) systems in power plants use Hastelloy C276 for scrubbers, ducts, and dampers due to its resistance to sulfur compounds.

Marine Engineering

Its resistance to seawater corrosion makes Hastelloy C276 suitable for seawater cooling systems, desalination plants, and offshore platforms.

Pulp and Paper Industry

Bleaching vessels and digesters employ Hastelloy C276 to handle chlorine-based chemicals.

Mining and Metallurgy

Used in autoclaves and acid leaching equipment due to its resistance to acidic slurries.

Pharmaceuticals

Ensures hygienic, corrosion-resistant performance in drug manufacturing equipment.

Comparison with Other Alloys

  • Hastelloy C276 vs Stainless Steel: C276 offers far superior corrosion resistance, especially in chloride environments.

  • Hastelloy C276 vs Inconel Alloys: Inconel performs better at extremely high temperatures, while C276 is unmatched in aggressive chemical environments.

  • Hastelloy C276 vs Titanium: Titanium is excellent for seawater applications, but C276 handles a broader range of acids and industrial chemicals.

Standards and Specifications

Hastelloy C276 is covered by multiple international standards:

  • ASTM B575: Plates, sheets, and strips

  • ASTM B574: Bars and rods

  • ASTM B619/B622: Seamless and welded pipes

  • ASTM B626: Welded tubes

  • ASME Boiler and Pressure Vessel Code for critical applications

Market Demand and Supply

With industries moving toward safer and more durable solutions, demand for Hastelloy C276 continues to rise worldwide. Suppliers like sasaalloy play a vital role in delivering certified, high-quality C276 products that meet ASTM and ASME standards. By partnering with sasaalloy, companies gain access to reliable materials designed for the most demanding conditions.

Conclusion

Hastelloy C276 (UNS N10276) is one of the most versatile and corrosion-resistant alloys available today. With its excellent balance of mechanical strength, resistance to both oxidizing and reducing agents, and weldability, it is an essential material for industries dealing with harsh chemicals and extreme environments.

From chemical processing and pollution control to marine engineering and pharmaceuticals, Hastelloy C276 continues to provide unmatched performance and safety. For engineers and procurement teams seeking a long-term solution, Hastelloy C276 remains a trusted choice for critical applications.

Post time: Aug-20-2025