The term superalloy was first used shortly after World War II to describe a group of alloys developed for use in turbo superchargers and aircraft turbine engines that required high performance at elevated temperatures.

An alloy is a solid solution or homogeneous mixture of two or more elements, at least one of which is a metal, which itself has metallic properties. It usually has different properties from those of its component elements. Alloying one metal with others often enhances its properties. The physical
properties, such as density, reactivity, Young’s modulus and electrical and thermal conductivity of an alloy may not differ greatly from those of its elements. However the engineering properties, such as tensile strength and shear strength may be substantially different from those of the constituent materials. These specialised alloys are exceptionally strong, lightweight, exhibit excellent mechanical strength, creep resistance at high temperatures, good surface stability, corrosion and oxidation resistance and therefore able to withstand extremes that would destroy everyday metals like steel and aluminium.

Key properties of superalloys are they are exceptionally strong, light weight, ehibit excellent mechanical strength, creep resistance at high temperatures, good surface stability and have corrosion and exidation resistance

Demand for Superalloys

It is estimated that the global specialty alloy market, including stainless steels, general purpose nickel alloys and high-performance nickel and cobalt-based alloys, represents total production volume of approximately 38.5 billion pounds per annum
(Haynes International Annual Report 2007).

The three industries that consume the most superalloy products are the:

• aerospace industry—principally jet engine
• the land-based turbine business, and
• the chemical process industry

The principal cost element in the production of superalloys is the cost of the nickel or cobalt. Since none of the worldwide producers of superalloy products produces nickel, all of them have to buy their raw material on the open market from the same primary or secondary (scrap) suppliers. Maintaining a competitive position therefore
relies on managing operating costs and maintaining a competitive lead in state-of the-art technology, both of which require continuing R&D on new and constantly evolving compositions and processing technologies.

Given the technologically advanced nature of the products, strict requirements of the end users and higher-growth end markets, it is believed that the high-performance alloy sector provides greater growth potential, higher profit margins and greater
means for service, product and price differentiation than stainless steels and general purpose nickel alloys.

Growth in worldwide demand is expected for high-performance alloys in the next ten years, based upon increasing demand in aerospace, chemical processing and land based gas turbine markets.