An alloy is a metal created by combining two or more metallic elements. Alloys provide enhanced properties in critical areas such as corrosion and wear protection, friction reduction, electrical conductivity and heat resistance While many metals offer these characteristics in their base form, developing alloys will augment the performance of each metal and improve overall results. Typical examples of metal alloys you’re undoubtedly familiar with include bronze (produced by combining copper and tin) and brass (a combination of copper and zinc).
A superalloy, also referred to as a high-performance alloy, is an enhanced version of an alloy that exhibits more robust characteristics for heavy-duty metal finishing applications. Specifically, superalloys provide increased thermal protection, greater surface stability, more corrosion protection and higher levels of mechanical strength. Consequently, superalloys are well-suited for high-stress manufacturing applications, such as when producing turbine engines for the aerospace industry.
The Need for Superalloys for Aircraft Turbine Engines
When you think of an airplane or spacecraft engine, the first things that probably come to mind are their size and power, as well as the deafening sound they make while operating. These engines also generate a substantial amount of heat. A jet engine, for example, can reach a temperature of more than 2,700 degrees Fahrenheit. A standard base metal or alloy cannot provide adequate thermal protection against such extreme temperatures.
The good news for aircraft manufacturers is that several superalloys are available that can withstand the extreme heat generated by turbine engines. These are typically nickel-based materials such as:
- Inconel: Developed in Great Britain by Wiggin Alloys in the 1940s, Inconel is a nickel-chromium alloy that works well in high heat applications, such as those involving aircraft turbine engines. Inconel also provides good corrosion protection.
- Monel: This superalloy features a blend of nickel with other metals such as titanium, copper, aluminum and iron. Monel works well in aerospace applications because it will maintain its strength at high temperatures.
The Benefits of Electroplating Aerospace Superalloys
Electroplating is an important finishing step for many metal-based products, including the superalloys used to manufacture aerospace turbine engines. Plating can enhance the properties of the superalloy and increase heat and corrosion resistance. However, only a few companies can deliver consistent results when executing this challenging process. Plating onto Inconel, for example, requires extensive surface preparation consisting of cleaning and pre-processing. The precise application of the coating (typically nickel) is essential — there is little margin for error when plating onto superalloy substrates.
SPC is one of the handful of U.S.-based metal finishing operations that has perfected the technique of plating onto superalloys for aircraft turbine engines. We’ll tap into our more than 90 years of expertise to develop a custom process for your manufacturing applications.
Contact us for more information and a no-obligation quote today.
