Monel 400
It is the most widely used and representative grade of Monel alloy, with a nickel content of approximately 63%–70% and a copper content of 28%–34%, supplemented by trace amounts of iron, manganese, and silicon. It exhibits outstanding corrosion resistance in seawater, hydrofluoric acid, and alkaline solutions, and also has good mechanical properties at both room and low temperatures. It is commonly applied to manufacturing marine components, chemical valves, pumps, and heat exchangers.
Monel K-500
Based on the composition of Monel 400, it is added with aluminum (around 2.3%–3.15%) and titanium (around 0.35%–0.85%). After precipitation hardening treatment, its strength and hardness are significantly improved compared with Monel 400, while retaining excellent corrosion resistance similar to Monel 400. This grade is suitable for high-strength and corrosion-resistant scenarios, such as aircraft engine parts, marine propeller shafts, and oil well drilling equipment.
Monel R-405
It is a free-machining variant of Monel 400, with a small amount of sulfur added to improve its machinability. It maintains the basic corrosion resistance of Monel 400 and is designed for components that require a large number of machining operations, such as precision mechanical parts and fasteners used in corrosive environments.
Monel 401
This grade has a nickel-copper ratio close to Monel 400 and is characterized by good magnetic permeability and corrosion resistance. It is mainly used in the manufacture of magnetic components that work in corrosive environments, such as sensors and magnetic shielding parts in marine or chemical equipment.
Monel 404
It is a low-carbon variant of Monel alloy, with extremely low carbon content controlled below 0.02%. It is specially developed for welding applications, which can effectively avoid the precipitation of carbides at the grain boundaries during welding and prevent intergranular corrosion, making it suitable for welded structural parts in harsh corrosive environments.
