Monel K-500, UNS N05500, is Monel 400 with aluminum and titanium added so it can be age hardened. Strength roughly triples over the base alloy while the nickel copper corrosion resistance, particularly in seawater, is retained.
It is a standard material for marine pump and propeller shafts, fasteners, valve stems and oilfield hardware, and it is essentially non magnetic.
Stocked as bar, forgings and wire in the annealed or age hardened condition.
Sizes and stock
- Round bar: up to 10" DIA
- Sheet / plate: up to 3" THK
- Forgings and custom shapes: by request
Processing capabilities
- Billet conversion and open die, closed die and ring forging
- Solution treat, age and anneal to the applicable spec
- Saw cutting, trepanning, gun drilling and CNC machining
- Ultrasonic, penetrant dye, micrography and physical testing
Specifications
Material is released to the applicable specification with mill test reports and, on request, independent lab verification.
Why engineers specify Monel K-500
- High strength with nickel copper seawater corrosion resistance
- Essentially non magnetic
- Resists cavitation and erosion in flowing seawater
- Age hardenable after machining
Nominal chemistry
Percent by weight, nominal composition per the governing specification. The mill test report for your heat is the controlling document.
Typical mechanical properties
| Condition | Tensile strength | Yield strength | Elongation | Hardness |
|---|---|---|---|---|
| Annealed | ~100 ksi | ~50 ksi | ~35% | - |
| Age hardened | 140 ksi min | 100 ksi min | 20% min | ~300 HBW |
Typical published values for reference only, not for design. Properties vary with section size, product form and processing. Order to the specification and condition your drawing requires.
Typical applications
- Marine propeller and pump shafts
- Valve stems and fasteners
- Oilfield drill collars and instruments
- Doctor blades and scrapers
Fabrication notes
Machining
Nickel and cobalt superalloys work harden aggressively. Use rigid setups, sharp tooling, slow speeds, positive feed that stays under the hardened skin, and flood coolant. Age hardened material machines far more slowly than solution treated material, so rough before aging wherever the print allows.
Welding
Most solid solution grades weld readily with matching filler. Age hardenable grades such as 718 and Waspaloy are welded in the solution treated condition and aged afterward to control strain age cracking.
Forming
Hot working ranges are narrow and forces are high. Cold form in the annealed condition with intermediate anneals, and stress relieve before final heat treatment.
Monel K-500 compared with similar grades
Monel 400
Same corrosion resistance, not hardenable, much lower strength.
Inconel 625
Better resistance to oxidizing acids, different strength mechanism.
Designations and cross reference
- Material family
- Nickel & Cobalt Alloys
- UNS number
- N05500
- Werkstoff (W.Nr)
- 2.4375
Working from an obsolete, foreign or superseded designation? Send it over and we will cross reference it to a current grade and specification.
Quality, testing and traceability
Supplied with mill test reports and heat traceability, with ultrasonic inspection, penetrant dye, micrography, grain size, stress rupture and mechanical testing available on request.
We are AS9100D and ISO 9001:2015 registered. If our stock does not already carry the inspection your specification requires, we can quote the material with that work performed. More on our quality system
Available forms
Custom sizes converted from billet, plus saw cut, waterjet and near-net blanks. See custom conversions
Monel K-500 frequently asked questions
What is Monel K-500?
Monel K-500, UNS N05500, is Monel 400 with aluminum and titanium added so it can be age hardened. Strength roughly triples over the base alloy while the nickel copper corrosion resistance, particularly in seawater, is retained.
What forms is Monel K-500 available in?
We supply Monel K-500 in bar, sheet, plate, forging. Custom sizes are converted from billet, and we can provide saw cut, waterjet or near net blanks so material arrives closer to your finished part.
What is the UNS or equivalent designation for Monel K-500?
Monel K-500 is designated UNS N05500, Werkstoff 2.4375. If your drawing calls out an obsolete or foreign designation we can cross reference it and confirm the equivalent before you order.
What specifications can Monel K-500 be supplied to?
Commonly ordered specifications include AMS 4676, QQ-N-286, UNS N05500. Material is released to the specification and condition on your purchase order, with mill test reports supplied as standard.
What conditions can Monel K-500 be ordered in?
We can supply Annealed, Age hardened. If our stock is not already in the condition you need, we can quote it with the heat treatment performed before shipment.
Can you cut Monel K-500 to size?
Yes. Saw cutting, waterjet, laser and shearing are available, along with trepanning, gun drilling, lathe turning and CNC machining, so you can order blanks or rough machined pieces rather than full lengths.
Do you provide test reports and additional testing on Monel K-500?
Every order ships with mill test reports and heat traceability. If your print calls for ultrasonic inspection, penetrant dye, magnetic particle, chemical assay, micrography, hardness or mechanical testing and our stock does not already carry it, we can quote the material with that work performed.
Can Monel K-500 be supplied to DFARS domestic melt requirements?
Tell us at quote stage if the order is DFARS or domestic melt restricted and we will confirm availability against that requirement before you commit.
What do you need to quote Monel K-500?
Grade, form, dimensions, quantity, specification and condition, plus any testing or certification requirements and the date you need it. Send a drawing if you have one. Quotes are typically ready within 24 hours.
How does Monel K-500 compare with Monel 400?
Same corrosion resistance, not hardenable, much lower strength.