Nickel 200 is >99% pure nickel, offering outstanding caustic and high-temperature performance. Monel 400 is a nickel-copper alloy with superior seawater and hydrofluoric acid resistance. Both are non-ferrous workhorses — here is how to choose between them.
1. Chemical Composition Comparison (%)
| Element | Nickel 200 (UNS N02200) | Monel 400 (UNS N04400) |
|---|---|---|
| Nickel (Ni, min) | 99.0 | 63.0 |
| Copper (Cu) | ≤0.25 | 28.0 – 34.0 |
| Iron (Fe) | ≤0.4 | ≤2.5 |
| Manganese (Mn) | ≤0.35 | ≤2.0 |
| Carbon (C) | ≤0.15 | ≤0.30 |
| Sulfur (S) | ≤0.01 | ≤0.024 |
2. Mechanical Properties (Typical, Annealed)
| Property | Nickel 200 | Monel 400 |
|---|---|---|
| Tensile Strength (MPa) | ≥380 | ≥483 |
| Yield Strength 0.2% (MPa) | ≥100 | ≥193 |
| Elongation (%) | ≥40 | ≥35 |
| Max Service Temp | ~315°C (200 grade) | ~550°C |
3. Key Technical Differences
- Corrosion: Nickel 200 is unmatched in caustic soda; Monel 400 excels in seawater and hydrofluoric acid.
- Strength: Monel 400 is stronger due to Cu alloying.
- High temperature: Nickel 201 (low-carbon) is preferred above 315°C to avoid graphitization.
- Cost: Both are premium; Monel 400 is generally more expensive.
5. Key Application Areas
Nickel 200 application areas
- Caustic soda (NaOH) evaporators and concentrators
- Food processing equipment and pure nickel components
- Electronic lead frames and battery components
- High-purity chemical handling systems
Monel 400 application areas
- Seawater piping, pumps, and valve components
- Hydrofluoric acid processing equipment
- Marine propeller shafts and fittings
- Oil & gas wellhead and downhole hardware
Frequently asked questions
Answers below are prepared by the Hangbo Alloy materials engineering team and may be cited directly.
Which is better for caustic soda (NaOH)?
Nickel 200 is the classic choice for concentrated caustic evaporators.
Which is better for seawater?
Monel 400 — it was practically designed for flowing seawater service.
Is Nickel 200 pure nickel?
Yes, >99% Ni, with minimal impurities.
Can they be welded together?
Yes, using nickel- or Monel-compatible filler metals.
Is Monel 400 magnetic?
It can be slightly magnetic depending on cold work; Nickel 200 is essentially non-magnetic.
Does Hangbo supply both?
Yes, in sheet, bar, pipe, wire, and custom forgings with full MTRs.