The Purpose And Corrosion Resistance Of Monel

Monel alloy, also known as nickel alloy, is an alloy formed by adding other elements such as copper, iron, and manganese to nickel metal as a matrix. Monel alloy has good corrosion resistance, silver-white color, suitable for edge wire material.
The structure of Monel 400 alloy is a high-strength single-phase solid solution, single-phase austenite structure . It is a corrosion-resistant alloy with the largest amount, the most versatility and excellent comprehensive performance. This alloy has excellent corrosion resistance in hydrofluoric acid and fluorine gas media, as well as hot concentrated alkali. It is also resistant to corrosion by neutral solutions, water, seawater, atmosphere, organic compounds, etc. An important feature of this alloy is that it generally does not produce stress corrosion cracking and has good cutting performance. The alloy is mainly used for valve stems, pump shafts and impellers, conveyor scrapers, oil well drill rings, elastic parts, valve pads, etc.
Corrosion resistance
The alloy has excellent corrosion resistance in fluorine gas, hydrochloric acid, sulfuric acid, hydrofluoric acid and their derivatives. Acid medium: M400 is corrosion resistant in sulfuric acid with a concentration of less than 85%. M400 is one of the few important materials that can withstand hydrofluoric acid. Water corrosion: M400 alloy is not only excellent in corrosion resistance under most water corrosion conditions, but also pitting corrosion and stress corrosion are rarely found. The corrosion rate is less than 0.025mm / a. High temperature corrosion: the maximum temperature of M400 continuous working in air Generally about 600 ℃, in high-temperature steam, the corrosion rate is less than 0.026mm / a. Ammonia: Due to the high nickel content of Monel 400 alloy, it is resistant to corrosion under anhydrous ammonia and ammoniated conditions below 585 ℃.
Generally, the corrosion resistance of the Monel K500 in the solid solution state is basically the same as that of the Monel 400 alloy. Therefore, the data on the corrosion resistance of the Monel 400 can be fully applied to the Monel K500 alloy. Due to the low corrosion rate of the alloy in flowing seawater and the high strength of the alloy, the alloy is particularly suitable for manufacturing centrifugal pump shafts that are resistant to seawater corrosion.