ASTM B407 UNS N08810 Nickel Alloy Steel Heat Exchanger Tube , Air Cooler

ASTM B407 UNS N08810 refers to a high-performance, nickel-based alloy that is specifically designed for use in heat exchanger tubes and other industrial applications where resistance to high-temperature corrosion, oxidation, and stress is required. The alloy is part of the broader family of nickel alloys, which are known for their excellent resistance to a wide variety of aggressive environments.

ASTM B407: This specification covers the requirements for nickel-alloy seamless and welded tubes, particularly for heat exchangers, condensers, and other heat transfer applications.

UNS N08810: The Unified Numbering System (UNS) designates this particular alloy as a high-chromium nickel alloy, well-suited to heat exchanger and similar applications.

Composition:

• Nickel (Ni): Approximately 35-46%, which is the primary element in the alloy.

• Chromium (Cr): Typically around 19-23%, contributing to high-temperature oxidation resistance.

• Iron (Fe): Around 20% (depending on specific grades), often found in nickel alloys to balance mechanical properties.

• Molybdenum (Mo): 2.5-3%, which enhances resistance to pitting, crevice corrosion, and improves mechanical properties.

• Other elements: Small quantities of silicon, manganese, and other trace elements are included for improved workability and resistance to various corrosive environments.

Mechanical Properties:

• High Strength: The alloy has excellent mechanical strength even at high temperatures, making it suitable for applications such as heat exchangers where the material is subjected to both thermal and mechanical stresses.

• Ductility and Toughness: It maintains good ductility and toughness, making it resistant to cracking or fracture under stress.

• Stress Corrosion Cracking Resistance: It is highly resistant to stress corrosion cracking, especially in environments like sulfuric acid and chloride.

Temperature Range:

• UNS N08810 can perform at elevated temperatures, typically up to 1100°F (593°C), with some variations depending on the specific environmental conditions.

• It is also capable of maintaining its mechanical properties in both high-temperature oxidizing environments and under moderate temperatures in corrosive atmospheres.