Ni-Cu K500 (UNS N05500)


Alloy K500 (Monel®) is a precipitation hardenable, nickel-copper-aluminum alloy that combines the excellent corrosion resistance of Alloy 400 with the added advantages of greater strength and hardness. 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. The thermal processing used to affect precipitation is commonly called age hardening or aging.

Typical industrial applications for Alloy K500 include fasteners, springs and chains for marine service, pump and valve components for chemical processing facilities, as well as blades and scrapers used in pulp and paper production. Oil and gas production utilize Alloy K500 for drill collars, instruments, pump shafts, impellers and valves as well as for sensors and electronic components.

Chemical Composition

Chemical Composition (wt%) limits as specified in ASTM B865*

Carbon 0.18 Iron 2.0
Nickel 63.0 min. Manganese 1.5
Copper 27.0-33.0 Silicon 0.5
Aluminum 2.30-3.15 Sulfur 0.010
Titanium 0.35-0.85    

*Maximum, unless range is indicated

Physical Properties

Physical properties for Alloy K500

Density, lb/in3 0.305
Modulus of Elasticity, psi 26 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 7.6 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 10
Specific Heat, Btu/lb ˚F 0.10
Electrical Resistivity, Microhm-in 24.2

Mechanical Properties

Mechanical property requirements as specified for hot worked and aged product in ASTM B865

Yield Strength, min. (ksi) 100
Tensile Strength, min. (ksi) 140
Elongation, min. (%) 20
Hardness, HRc 27


Typical standards for Alloy K500