UNS Number N05500

Monel K-500 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.

Available Forms of Monel K-500 at Rooplaxmi Steels:

•           Bar
•           Sheet
•           Plate
•           Pipe & Tube (welded and seamless)
•           Pipe Fittings
•           Wire

Characteristics of Monel K-500:

•           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

 

Monel K-500 Chemical Composition, %:

Ni	Cu	Al	Ti	Fe	Mn	S	C
63 min	27.0-33.0	2.3-3.15	0.35-0.85	2.0 max	1.5 max	0.01 max	0.25 max

Si

0.5 max

 

Application of Monel K-500:

•           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

 

Machining and 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.

 

Monel K-500 ASTM Specification:

Rod & Bar

AMS 4676

 

Mechanical Properties of Monel K-500:
           Typical Room Temperature Tensile Properties of Annealed Material

Product form	Condition	Tensile (ksi)	0.2 % Yield (ksi)	Elongation (%)
Rod & Bar	Hot-Finished/Aged	140-190	100-150	30-20
Rod & Bar	Hot Finished/Annealed	90-110	40-60	45-25
Rod & Bar	Hot Finished / Annealed/Aged	130-165	85-120	35-20
Rod & Bar	Cold-Drawn/Aged	135-185	95-160	30-15
Rod & Bar	Cold-Drawn/ Annealed/Aged	130-190	85-120	30-20
Plate	ot-Finished/Aged	140-180	100-135	30-20
Sheet	Cold-Rolled/ Annealed	90-105	40-65	45-25