Stainless steel is usually the first choice for applications needing corrosion resistance in their mechanical cable assemblies. But sometimes complex application requirements make stainless steel inappropriate to the task. Saltwater and very high temperatures for instance, are two conditions under which stainless steel may not be ideal. Because failure of any sort, once your product is in use, is not acceptable, you might want to look at Inconel®. Here are just a few ways this super stainless steel material elevates your product’s potential.
Inconel®: One of the Superalloys
While working on jet and rocket engines, scientists found they needed new alloys to endure the extreme temperatures produced in aerospace applications. This prompted the development of nickel-based “superalloys,” so-called because they exceeded the performance of other metals available. One of those superalloys was Inconel®.
Inconel® is composed primarily of nickel, chromium and molybdenum, plus other elements like iron. It's produced in a number of grades, each with slightly different proportions of these different elements. Its appearance is similar to stainless steel, although it is heavier, due to its slightly higher density. At 2,550 °F, the melting point of Inconel® is similar to that of stainless. This prompts the question: what makes Inconel® “super” then?
Answering that means delving deeper into the properties of Inconel®.
Consider Temperature Behavior
The strength of Inconel® varies considerably by alloy composition but is in the range of 80,000 to 135,000 psi at room temperature. Stainless, by comparison, is around 75,000 psi, making the two not too far apart.
The difference is that the strength of stainless steel drops off as temperatures rise. The limit at which stainless steel can be used is between 1,900 °F and 2,000 °F. In contrast, Inconel® retains its strength until much closer to its melting point. If you need a metal that will retain its strength at 2,000 °F, it has to be Inconel®.
Differences in Corrosion Resistance
Inconel® is one of the most corrosion-resistant of all metals. Its performance even exceeds that of stainless steel. Stainless steel is vulnerable to chlorine ions, such as salt, seawater and other corrosives, while Inconel® is virtually immune to such attacks. Likewise, both hydrochloric and sulfuric acid eat away at stainless steel, but hardly affect Inconel®. In addition, while the corrosion resistance of stainless steel lessens as temperatures increase, that of Inconel® declines little, if at all.
Inconel® Applications
Since it comes at a higher price point, Inconel® is used only when stainless steel lacks the capabilities required. Five industries in which this often occurs are:
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Oil and gas extraction
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Marine
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Waste processing
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Aerospace, including jet engines
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Automotive
All of these industries benefit from the high-temperature strength of Inconel®, but the first three also take advantage of the exceptional corrosion resistance properties of this material. “Downhole” oil well applications can encounter both high temperatures and strong acids. Marine environments expose metals to saltwater, which leaves Inconel® unscathed. Waste processing organizations also face a host of temperature and corrosive element challenges. Lastly, a somewhat more specialized area is that of swimming pools, where chlorine in the atmosphere can corrode stainless fixtures and fittings.
Choose Carl Stahl Sava Industries for Inconel® Cable
At Sava, we produce high-quality cables and mechanical cable assemblies for the most challenging applications and environments. When stainless steel can do the job, that's what we'll recommend you use. There are some applications, however that need more high-temperature strength or corrosion-resistance and sometimes both. And in these circumstances, stainless steel just will not do. In those cases, Sava provides customers with custom-made, Inconel® cable and cable manufacturing.
Contact us today to learn more about the Inconel® cable we produce, as well as cable we manufacture from other materials, such as tungsten, stainless steel, galvanized steel and more.
