Incoloy 800 Bars vs. Other Alloy Pipes: What Sets Them Apart?

In the ever-evolving world of industrial materials, the demand for reliable, high-temperature, and corrosion-resistant alloys is more pressing than ever. Among the many contenders, Incoloy 800 bars stand out as a trusted solution for engineers and procurement professionals dealing with extreme conditions. But how do they compare with other alloy pipes? What makes Incoloy 800 bars so unique?

In this comprehensive SEO article, we explore the fundamental differences between Incoloy 800 bars and other alloy pipes such as Inconel 600, Hastelloy C276, and stainless steel 316. We highlight the mechanical and chemical advantages of Incoloy 800 and demonstrate why it remains a go-to material in high-stakes industries like petrochemical, power generation, and aerospace.

What Is Incoloy 800?

Incoloy 800, also referred to by UNS N08800, is a nickel-iron-chromium alloy designed for high-temperature structural applications. It is known for its ability to resist oxidation, carburization, and other forms of high-temperature corrosion.

It is often used in its strengthened versions—Incoloy 800H (UNS N08810) and 800HT (UNS N08811)—which provide improved creep and rupture strength.

Chemical Composition of Incoloy 800 Bars

The typical chemical composition of Incoloy 800 is:

• Nickel (Ni): 30.0 – 35.0%

• Chromium (Cr): 19.0 – 23.0%

• Iron (Fe): Balance

• Carbon (C): ≤ 0.10%

• Aluminum (Al): 0.15 – 0.60%

• Titanium (Ti): 0.15 – 0.60%

• Manganese (Mn): ≤ 1.5%

• Silicon (Si): ≤ 1.0%

• Sulfur (S): ≤ 0.015%

This balanced composition ensures excellent strength and resistance to scaling at temperatures above 1000°F (538°C).

Mechanical Properties

Typical mechanical properties of Incoloy 800 bars include:

• Tensile Strength: ≥ 520 MPa

• Yield Strength (0.2%): ≥ 205 MPa

• Elongation: ≥ 30%

• Hardness: Approx. 150-180 HB

These figures are for annealed material, and properties can be enhanced through cold working or thermal treatment.

1. High-Temperature Resistance

Compared to stainless steels and other alloy pipes, Incoloy 800 bars offer exceptional resistance to high-temperature oxidation and scaling. This makes them suitable for prolonged exposure in furnaces, heat exchangers, and superheater tubing. While stainless steel 316 begins to suffer at temperatures above 800°C, Incoloy 800 performs reliably beyond this threshold.

For example:

• Incoloy 800: Up to 1100°C (intermittent service)

• Stainless Steel 316: Up to 870°C (intermittent service)

• Inconel 600: Similar high-temp resistance but more expensive

2. Resistance to Carburization and Nitridation

In environments where carburization or nitridation is a concern, such as ethylene production and hydrocarbon reformers, Incoloy 800 bars significantly outperform standard alloys.

This is due to the alloy’s high nickel and chromium content, which provides a strong protective oxide layer, reducing degradation and extending service life. This sets it apart from:

• Alloy 20: Excellent acid resistance but poor carburization resistance

• Hastelloy C276: Strong in chemical resistance but not designed for high carburization settings

3. Superior Structural Stability

Incoloy 800 bars retain microstructural integrity over long periods of exposure, even under thermal cycling. This stability helps prevent grain growth, phase separation, and embrittlement—common issues in other alloy materials used at elevated temperatures.

This feature is critical in:

• Waste heat recovery systems

• Oil and gas refinery components

• Boiler superheaters and headers

sasaalloy supplies Incoloy 800 bars that are heat-treated for enhanced grain stability, ensuring longevity and performance.

4. Corrosion and Oxidation Resistance

Incoloy 800 offers excellent general corrosion resistance in both acidic and basic environments. While it does not outperform Hastelloy C276 in reducing acids, it strikes a better balance of corrosion resistance, oxidation resistance, and thermal stability than most stainless steels or even Inconel 600 in certain conditions.