The primary disadvantage of Monel is its cost compared with many other metals. This is due to it being a range of nickel-based alloys, based on up to 67% nickel content. Nickel is one of the most expensive individual elements used in the production of corrosion resistant metals, and its price can also be quite volatile also.
For some applications it might be possible to substitute Monel for super duplex stainless steels, which offer similar levels of strength but at far lower costs. The corrosion resistance of super duplex stainless steels is good in seawater and many acids. However, the temperature operating range of super duplex stainless steels is far more limited than Monel grades. Therefore, if the intended application is to operate below -50degC or above 250degC then this might not be a suitable alternative.
So-called ‘Super Austenitic’ stainless steels, such as Alloy 254, can match the low temperature operating range of Monel grades, but provide far lower strengths. High-strength stainless steels such as Nit50 can match the strength levels and low temperature operating range, but without the level of corrosion resistance of Monel.
Although stainless steels and some other nickel-based grades such as Alloy 825 offer significant cost savings over Monel grades, they are unable to match the performance of Monel across lower and higher temperatures, and in very aggressive environments found within the chemical processing industry, Oil and Gas, and marine applications.
Langley Alloys stocks Alloy K-500 as round bars from 5/8”-10” diameter (15.87-254mm).
For more information about our range of alloys, please contact Langley Alloys today.