Description

Alloy 825 is a nickel-iron-chromium alloy known for its exceptional corrosion resistance in various corrosive environments. It exhibits excellent resistance to both reducing and oxidizing acids, as well as stress corrosion cracking in chloride-containing environments.

Applications

As an alloy with outstanding corrosion resistance, Alloy 825 finds extensive application in industries such as chemical processing, oil and gas production, pollution control, and marine engineering. It is commonly used for heat exchangers, piping systems, tanks, valves, and fittings where resistance to corrosion and high temperatures is crucial.

Blacksmith Applications

For blacksmiths, Alloy 825 presents a unique opportunity to create specialized tools that require exceptional corrosion resistance. This alloy can be utilized to craft various custom tools such as chisels, hammers, and tongs, particularly in environments where exposure to corrosive chemicals or high temperatures is a concern.

Alloy 825 Forging Temperature

Forging of Alloy 825 is typically carried out between 2050°F - 2200°F (1121°C to 1204°C), followed by air cooling or rapid quenching to retain the alloy's desirable properties.

Alloy 825 Heat Treatment

Alloy 825 Annealing Temperature

Annealing this alloy is typically performed at 1600°F to 1900°F (871°C to 1038°C), with a suitable hold time, followed by water quenching or rapid air cooling.

Alloy 825 Normalizing Temperature

Normalizing can be performed by heating Alloy 825 to 1700°F to 1900°F (927°C to 1038°C) and cooling it in still air or by a faster method like air blast or water quenching.

Alloy 825 Hardening Temperature

Alloy 825 does not respond to conventional heat treatment hardening methods. Surface hardening techniques such as nitriding or carburizing can be employed to improve the alloy's hardness.

Alloy 825 Tempering Temperature

Tempering is not applicable for Alloy 825 as it does not require further heat treatment to achieve desired properties.

Machinability

Alloy 825 has a machinability rating of approximately 20-30% compared to free-cutting carbon steel. It requires special cutting tools, low surface feed rates, and ample coolant to achieve satisfactory machining results.

Weldability

Alloy 825 has good weldability. It can be welded using various fusion and resistance welding techniques. However, it is important to consider proper cleaning, preheating, and post-weld heat treatment to ensure corrosion resistance and mechanical properties in the welded joints.