Alloy K-500, UNS NO5500
alloy K-500 which is produced by adding aluminum and titanium to the basic MONEL nickel-copper composition also has a face-centered cubic structure. In the age-hardened condition a submicroscopic gamma prime Ni3Al phase is formed throughout the matrix.
Alloy k500 has excellent corrosion resistance in an extensive range of natural and chemical environments, excellent resistance to chloride-ion stress-corrosion cracking and very high strength and hardness.After age-hardening, Alloy K500 has approximately 2 to 3times higher mechanical properties than the nickel-copper alloy (Monel 400), high tensile properties up to about 650℃，good corrosion fatigue resistance and ow permeability with non-magnetic down to -135℃.
In general, the corrosion resistance of Alloy K500 is similar to that of Alloy 400. Excellent resistance is shown to a wide range of media from pure water to mineral acids, salts and alkalis. Alloy K500 is virtually immune to chloride-ionstress-corrosion cracking. In the aged condition, the alloy may be susceptible to stress-corrosion cracking in most, aerated hydrofluoric acid vapour at stresses near the yield strength. In high-velocity seawater and in marine atmospheres, good corrosion resistance is shown but, in slow-moving or stagnant seawater, pitting may occur. Nicorros Al also shows good resistance in sour-gas environment.
Alloy K500 finds wide application in the marine, chemical, petrochemical and shipbuilding industries.Typical applications include;
1. Valve seals, pump sleeves and wear rings in marine environments-high strength and resistance to seawater.
2. Doctor blads and scrapers;
3. Fasteners, e.g. Bolts, used in marine atmospheres and tidal waters - resistance to chloride-containing environments;
4. Towing cable armouring - high strength, non-magnetic properties and resistance to seawater;
5. Oil well drilling equipment such as non-magnetic drill collars, valves and instrumentation sleeves - resistance to chloride-containing nedia and sour-gas environments'
6. Springs - resistance to a variety of corrosive media;
7. Aviation instrument components - non-magnetic.