Superalloys - An Introduction

Background

The name “superalloy” refers to metals that have been developed to withstand high temperatures without deforming (including creep) or corroding. Many of these have been developed for use in applications such as gas turbine and jet engines, more specifically in areas where extreme heat is encountered. Hence, it comes as no surprise that approximately 75% of superalloys are used in aerospace applications, of which civilian transport has been identified as a growth area over the next twenty years.

Due to their ability to withstand deformation at high temperatures, they are inherently non-ductile and consequently difficult to hot and cold work.

To achieve the properties required to be classified as a “superalloy”, they usually have high proportions of refractory alloying agents such as nickel and cobalt.

Some examples of superalloy families are given in the following table.

Applications

Applications of superalloys include:

•         Vanes and blades for jet and gas turbine engines

•         Heat exchangers

•         Components for chemical reaction vessels

•         Equipment for heat treatment.

Primary author: AZoM.com