Difference between Monel 400 And Monel K500 Round Bars

Monel is an alloy based on nickel 65-70 percent and copper 20-29 percent and also contains iron and manganese up to 5 percent and other compounds. Monel can be divided into various grades such as Monel 400, K500, R-405 depending on the proportion of various elements. In this article, we are going to discuss the various advantages and applications of Monel Round Bars.


Monel 400 Round Bars contain about 67 percent Nickel, 23 percent Copper and they are resistant to seawater and steam at high temperatures as well as to salt and caustic solutions. Monel 400 Round Bars exhibit characteristics like good corrosion resistance, good weldability, and high strength. It is widely used in marine applications and other non-oxidizing chloride solutions due to low corrosion rate in rapidly flowing brackish or seawater combined with excellent resistance to stress-corrosion cracking in most freshwaters, and its resistance to a variety of corrosive conditions. Monel 400 Round Bars are particularly resistant to hydrochloric and hydrofluoric acids when they are de-aerated. Monel 400 has great mechanical properties at subzero temperatures, can be used in temperatures up to 1000 degrees F, and it is melting point is 2370-2460 degree F.

Application of Monel 400 Round Bars are as follows:-

• Marine engineering
• Chemical and hydrocarbon processing equipment
• Gasoline and freshwater tanks
• Crude petroleum stills
• De-aerating heaters
• Boiler feedwater heaters and other heat exchangers
• Valves, pumps, shafts, fittings, and fasteners
• Industrial heat exchangers
• Chlorinated solvents
• Crude oil distillation towers


Monel K500 Round Bars are precipitation-hardenable nickel-copper alloy bars that combine the excellent corrosion resistance characteristic of Monel 400 with the added advantage of greater strength and hardness. These modified 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. Monel K-500 Bars have a greater tendency toward stress-corrosion cracking in some environments than Monel 400. Monel K-500 Bars have 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 degree F but stays ductile and tough down to temperatures of 400 degrees F. Its melting range is 2400-2460 degrees F.

Application of Monel K500 Round Bars are as follows:-

• 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