A nickel-copper alloy called Monel 400, constituting 67% Ni & 23% Cu, is resistant to salt and caustic solutions, as well as sea water and steam at high temperatures. The only way to harden Monel 400 is through cold working because it is a solid solution alloy. High strength, outstanding weldability, and strong corrosion resistance are all features of this nickel alloy.
Monel 400 offers excellent corrosion resistance to:
Monel 400 has poor resistance to nitric acid & ammonia systems.
It has varied applications in marine engineering, chemical & hydrocarbon processing equipment, crude petroleum stills, etc.
Chemical Composition:
| Element | Percentage |
|---|---|
| Nickel ( Ni ) | 65% |
| Copper ( Cu ) | 30% |
| Aluminium ( Al ) | 2.3% - 3.1% |
| Iron ( Fe ) | 2% |
| Other: | |
| Titanium ( Ti ) | 0.35%-0.85% |
| Carbon ( C ) | 0.3% |
Corrosion Rating:
RATINGS - 0:Unsuitable 1:Poor to Fair 2:Fair 3:Fair to good 4:Good 5:Good to Excellent 6:Normally Excellent
| Materials | Non-oxidizing or reducing media | Liquids | Gases | |||||||
| Acid solutions excluding Hydrochloric, phosphoric, sulfuric | Neutral solutions, e.g. many Non-oxidizing salt solutions, chlorides, sulfates | Alkaline solutions | Oxidizing Media | Halogen & derivatives | ||||||
| Caustic & mild alkalis, excluding ammonium hydroxide | Ammonium hydroxide & amines | Acid solutions, e.g. nitric | Neutral or alkaline solutions e.g. per sulfates, peroxides, chromates | Pitting media, acid ferric chloride solutions | Halogen | Hydrogen halides, dry, e.g., dry, hydrogen chloride | ||||
| Moist, e.g. chlorine below dew point | Dry, e.g. fluorine above dew point | |||||||||
| Alloy 400 | 5 | 6 | 6 | 1 | 0 | 5 | 1 | 2 | 6 | 3 |
Note: Maximum Design Temperature: 482°C