Materials / Nickel alloy

Monel K-500

UNS
N05500
W.Nr
2.4375
EN
NiCu30Al

Age-hardenable Monel, using aluminium and titanium to roughly triple the yield strength of 400 while keeping its seawater performance.

Composition

Chemical composition limits, per cent by weight
ElementMinMax
Ni 63.0
Cu 27.0 33.0
Al 2.30 3.15
Ti 0.35 0.85
Fe 2.0
Mn 1.5
C 0.25

Per cent by weight, to the governing standard.

Nominal composition
  • Ni66.7
  • Cu30.0
  • Al2.7
  • Ti0.6

Per cent by weight, at the midpoint of each specified window. Elements given only as a maximum have no midpoint to take, so they sit inside the balance rather than being estimated; trace elements below 0.5 % are not shown. Indicative only; the composition table above and the governing standard are what define the limits.

Mechanical

Tensile strength, min
965 MPa
Yield strength (0.2%), min
690 MPa
Elongation, min
20 %
Condition
Age hardened — condition to be specified on order

Standards by form

Governing standard for each product form
Bar, rod & forgings ASTM B865
Fasteners ASTM F467 / F468

Where it is specified

  • Pump shafts, propeller shafts, fasteners and valve stems in marine service
  • Strength of a structural alloy with the corrosion behaviour of Monel 400
  • Non-magnetic and spark-resistant

Over-ageing buys strength and hydrogen embrittlement together

K-500 is vulnerable to hydrogen embrittlement if over-aged or over-hardened, which makes the heat treatment record and the hardness result the safety-critical documents. Aluminium below the 2.30 % floor means the age hardening cannot reach specified strength.

What we specify and check

  • Hardness verification on the delivered material
  • Heat treatment records demanded and read
  • PMI for Al and Ti against B865

We commission an accredited independent laboratory to test the heat before the material leaves China. You will receive that report unedited, whether it passes or not.

Request Monel K-500

Tell us the form, dimensions and service conditions. We reply with availability, indicative landed price, lead time and the test regime we would specify for your application.

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