Monel 400 alloy in the fluoride gas, hydrochloric acid, sulfuric acid and their derivatives have a very good corrosion resistance property, and possess better corrosion resistance more than the copper alloy in the sea water. Acid medium: Monel 400 has corrosion resistance in less than 85% consistency of sulfuric acid. Monel 400 is an important material that resistant to . Water corrosion: Monel 400 alloy in most corrosion cases of water, not only excellent corrosion resistance, but also less pitting, stress corrosion, the corrosion rate less than 0.025mm / a. High temperature corrosion: Monel 400 for the work of the highest temperature at about 600 °C in general in the air, in the high temperature steam, the corrosion rate less than 0.026mm / a. Ammonia: Monel 400 can be resistant to an hydrous ammonia and aminate conditions corrosion below 585 °C due to the high nickel.