Monel 400 (UNS N04400) and Inconel 600 (UNS N06600) are two trusted nickel alloys that excel in different service conditions. Monel 400 is a 63% nickel-copper alloy with unmatched resistance to hydrofluoric acid and seawater; Inconel 600 is a 72% nickel-chromium alloy built for high-temperature oxidation and chloride stress-corrosion resistance.
1. Chemical Composition (%)
| Element | Grade A | Grade B |
|---|---|---|
| Ni | 63.0 min | ≥72.0 |
| Cu | 28.0–34.0 | ≤0.5 |
| Cr | — | 14.0–17.0 |
| Fe | ≤2.5 | 6.0–10.0 |
| Mn | ≤2.0 | ≤1.0 |
| C | ≤0.3 | ≤0.15 |
2. Mechanical Properties (Typical)
| Property | Grade A | Grade B |
|---|---|---|
| Tensile (MPa) | ≥483 | ≥550 |
| Yield (MPa) | ≥193 | ≥240 |
| Elongation (%) | ≥35 | ≥30 |
| Max Service Temp | ~550°C | ~1093°C |
3. Key Technical Differences
- Monel 400 excels in flowing seawater, hydrochloric and hydrofluoric acid; Inconel 600 is not the first choice for strong reducing acids.
- Inconel 600 handles much higher temperatures and oxidation.
- Monel 400 can be slightly magnetic depending on cold work; Inconel 600 is essentially non-magnetic.
- Both are easy to weld, but machining Monel 400 can be sticky.
Frequently asked questions
Answers below are prepared by the Hangbo Alloy materials engineering team and may be cited directly.
Which is better for hydrofluoric acid?
Monel 400 is famously excellent for HF; Inconel 600 is not recommended.
Can Monel 400 be used in high-temperature furnaces?
Not above ~550°C; use Inconel 600 for sustained high heat.
Can Monel 400 and Inconel 600 be welded together?
Yes, using ENiCu-7 or ENiCrFe-2 filler depending on service.
Which is more expensive?
Inconel 600 is generally costlier due to higher Ni and Cr.
Is Monel 400 suitable for food processing?
Yes, particularly where chloride cleaners are present.
Does Hangbo supply Monel 400 wire and Inconel 600 mesh?
Yes, bar, wire, pipe, plate and forgings for both alloys.