UNS N05500
Other common names: Alloy K500
Monel K500 is a precipitation-hardenable nickel-copper alloy that
combines the excellent corrosion resistance characteristic of Monel
400 with the added advantage of greater strength and hardness.
These amplified properties, strength and hardness, are obtained by
adding aluminum and titanium to the nickel-copper base and by a
thermal processing used to effect precipitation, typically called
age hardening or aging. When in the age-hardened condition, Monel
K-500 has a greater tendency toward stress-corrosion cracking in
some environments than Monel 400. Alloy K-500 has approximately
three times the yield strength and double the tensile strength when
compared with alloy 400. Plus, it can be further strengthened by
cold working prior to precipitation hardening. The strength of this
nickel steel alloy is maintained to 1200° F but stays ductile and
tough down to temperatures of 400° F. Its melting range is
2400-2460° F.
This nickel alloy is spark resistant and non-magnetic to
-200 F. However, it is possible to develop a magnetic layer on
the surface of the material during processing. Aluminum and copper
may be selectively oxidized during heating, leaving a magnetic
nickel rich film on the outside. Pickling or bright dipping in acid
can remove this magnetic film and restore the non-magnetic
properties.
In what forms is Monel K500 Available?
• Bar
• Rod
Corrosion Resistant Monel K-500
The corrosion resistance of alloy K-500 is substantially equivalent
to that of alloy 400 except that when in the age-hardened
condition, nickel alloy K-500 has a greater tendency toward
stress-corrosion cracking in some environments. Monel K-500 has
been found to be resistant to a sour-gas environment. The
combination of very low corrosion rates in high-velocity sear water
and high strength make alloy K-500 particularly suitable for shafts
of centrifugal pumps in marine service. In stagnant or slow-moving
sea water, fouling may occur followed by pitting but this pitting
slows down after a fairly rapid initial attack.
What are the characteristics of Monel K500?
• Corrosion resistance in an extensive range of marine and chemical
environments. From pure water to non-oxidizing mineral acids, salts
and alkalis.
• Excellent resistance to high velocity sea water
• Resistant to a sour-gas environment
• Excellent mechanical properties from sub-zero temperatures up to
about 480C
• Non-magnetic alloy
Chemical Composition, %
Ni | Cu | Al | Ti | C | Mn | Fe | S | Si |
63.0-70.0 | Remainder | 2.30-3.15 | .35-.85 | .25 max | 1.5 max | 2.0 max | .01 max | .50 max |
In what applications is Monel K-500 used?
• Sour-gas service applications
• Oil and gas production safety lifts and valves
• Oil-well tools and instruments like drill collars
• Oil well industry
• Doctor blades and scrapers
• Chains, cables, springs, valve trim, fasteners for marine service
• Pump shafts and impellers in marine service
Fabrication with Monel K-500
Monel K-500 is readily fabricated by standard commercial
procedures.
Welding alloy K-500 is best accomplished by the gas-tungsten-arc
welding process. It is recommended that Monel K-500 be annealed
when it is welded and that any weldments be stress relieved prior
to aging.
Heavy machining of this alloy is best accomplished when the
material is in the annealed condition or hot-worked and quenched
condition. Age-hardened material however can be finish-machined to
close tolerances and fine finishes. Therefore, the recommended
practice is to machine slightly oversize, age-harden, then finish
to size. During aging, a slight permanent contraction takes place,
but little warpage occurs because of the low temperatures and slow
cooling rates involved.
Specifications
Mechanical Properties
Typical Room Temperature Tensile Properties of Annealed Material
Product Form | Condition | Tensile (ksi) | .2% Yield (ksi) | Elongation % | Hardness |
Rod & Bar | Hot-Finished/Aged | 140-190 | 100-150 | 30-20 | 27-38 HRC |
Rod & Bar | Hot Finished/Annealed | 90-110 | 40-60 | 45-25 | 75-90 HRB |
Rod & Bar | Hot Finished/Annealed/Aged | 130-165 | 85-120 | 35-20 | 24-35 HRC |
Rod & Bar | Cold-Drawn/Aged | 135-185 | 95-160 | 30-15 | 25-41 HRC |
Rod & Bar | Cold-Drawn/Annealed/Aged | 130-190 | 85-120 | 30-20 | 24-35 HRC |
Plate | Hot-Finished/Aged | 140-180 | 100-135 | 30-20 | 27-37 HRC |
Sheet | Cold-Rolled/Annealed | 90-105 | 40-65 | 45-25 | 85 HRB Max |
We can provide Monel K-500 material in the form of flange,
fittings, pipes, fasteners.