Oxidized Incoloy 800H Plate

Updated: 2026-07-21

Overview

Incoloy 800H is a nickel-iron-chromium alloy engineered for high-temperature applications where oxidation and carburization resistance are critical. It is a variant of Incoloy 800 with controlled carbon content for improved creep rupture strength. The alloy is widely used in industries requiring durable materials under extreme thermal and chemical conditions. Developed in the mid-20th century, Incoloy 800H has become a standard material for industrial heating equipment and chemical reactors. Its balanced composition (typically 30-35% nickel, 19-23% chromium) ensures stability in environments up to 1100°C, making it a preferred choice for demanding applications.

Physical and Chemical Properties

Incoloy 800H exhibits exceptional mechanical properties at elevated temperatures, including a tensile strength of approximately 500 MPa at room temperature. Its high chromium content provides robust oxidation resistance, while nickel ensures stability in reducing environments. The alloy's thermal expansion coefficient is comparable to carbon steel, simplifying integration into existing systems. Key chemical properties include resistance to sulfur compounds, nitric acid, and alkaline solutions. However, it is less suitable for hydrochloric or sulfuric acid exposure. The controlled carbon content (0.05-0.10%) enhances creep resistance without compromising weldability, a critical factor for fabricators.

Main Applications

The primary use of Incoloy 800H steel plates is in high-temperature industrial equipment. Common applications include radiant tubes, muffles, and retorts in heat treatment furnaces, where temperatures routinely exceed 800°C. Petrochemical plants utilize it for pyrolysis furnace components and reformer tubes due to its carburization resistance. In power generation, the alloy is specified for superheater and reheater tubing in boilers. The nuclear industry employs it for heat exchangers and steam generator parts. Recent innovations have expanded its use in renewable energy systems, particularly concentrated solar power (CSP) plants.

Safety and Storage

While Incoloy 800H is not classified as hazardous, proper handling precautions are essential. Machining operations generate fine metallic dust requiring local exhaust ventilation. Hot working should be performed in controlled environments to prevent scaling, typically at 870-1230°C for forging. Storage recommendations include keeping plates separated by protective material to prevent surface damage. Indoor storage is preferred to avoid chloride-induced stress corrosion cracking. For long-term storage, application of volatile corrosion inhibitors (VCI) is advisable, especially in coastal regions with high humidity.

B2B Procurement Guide

When sourcing Incoloy 800H plates, buyers should specify the required ASTM standard (typically B409 for plates/sheets). Key procurement considerations include mill test reports verifying chemical composition and mechanical properties. Lead times can range from 4-12 weeks for standard sizes, longer for custom dimensions. Quality verification should include ultrasonic testing for critical applications. Competitive pricing is typically available for orders exceeding 5 metric tons. Buyers are advised to confirm the supplier's capability to provide traceable material certifications and their experience with high-nickel alloy processing.