Designated as UNS N05500 or DIN W.Nr. 2.4375, Monel K-500 (also known as “Alloy K-500”) is a precipitation-hardenable nickel-copper alloy that combines the corrosion resistance of Monel 400 (Alloy 400) with greater strength and hardness. It also has low permeability and is nonmagnetic to under -100°C[-150°F]. The increased properties are obtained by adding aluminum and titanium to the nickel-copper base, and by heating under controlled conditions so that submicroscopic particles of Ni3 (Ti, Al) are precipitated throughout the matrix. Monel K-500 is used primarily for pump shafts, oil well tools and instruments, doctor blades and scrapers, springs, valve trims, fasteners, and marine propeller shafts.
| The Chemical Composition of Monel K500, % | |
|---|---|
| Nickel | ≥63.0 |
| Copper | 27.0-33.0 |
| Aluminum | 2.30-3.15 |
| Titanium | 0.35-0.85 |
| Carbon | ≤0.25 |
| Manganese | ≤1.50 |
| Iron | ≤2.0 |
| Sulfur | ≤0.01 |
| Silicon | ≤0.50 |
| Density | Melting Range | Specific Heat | Electrical Resistivity | |
|---|---|---|---|---|
| g/cm3 | °F | J/kg.k | Btu/lb. °F | µΩ·m |
| 8.44 | 2400-2460 | 419 | 0.100 | 615 |
Monel K-500 can be furnished in the form of plate, sheet, strip, bar, rod, wire, forgings, pipe & tube, fittings and fasteners in accordance with relative standards such as ASTM B865, BS3072NA18, BS3073NA18, DIN 17750, ISO 6208, DIN 17752, ISO 9725, DIN 17751, and DIN 17754, etc. The regular welding process for Monel K-500 is gas tungsten arc welding(GTAW) with Monel filler metal 60. It can be readily hot formed or cold formed. The maximum hot working temperature is 2100°F while cold forming can only be accomplished on annealed materials. The regular heat treatment for Monel K-500 material usually involves both annealing (either solution annealing or process annealing) and age-hardening procedures.