What to Look for When Buying Metals & Alloys for High-Temperature Service & Applications

If your business works with alloys in hot environments, choosing the right alloys for a high-temperature service can be confusing. After all, there’s no such thing as uniformity when it comes to working in extreme temperatures.

The alloy you require will depend on the function it will serve. Here is a breakdown of some of the world’s most heat resistant metals and alloys as well as other factors to consider before you make a purchase.

What is a Heat Resistant Alloy?

Heat resistant alloys are alloys that perform well at high temperatures, which means they have high creep resistance and strength at high temperatures. The heat resistance levels of these alloys are confirmed by two physical properties, which are the structure of the alloy and the strength of the interatomic bonds within it.

Heat resistant alloys are classified by their base which could be nickel, iron, titanium, beryllium, and other metals.
Additionally, heat resistant alloys can also be divided into three categories based upon their operating environment: alloys that are subjected to small amounts of heat stress (seconds to minutes), alloys that are subjected to moderate amounts of heat stress (hours or hundreds of hours), alloys that are subjected to heat stress for long periods of time (thousands of hours).

Elements & Alloys That Can Withstand High Temperatures

1. Titanium

Titanium is a lustrous transition metal which is silver in colour.Titanium alloys have high tensile strength to weight ratio, good toughness, extraordinary resistance to corrosion and an ability to withstand extreme temperatures of 600°C plus. It is readily weldable and possesses good fabricability and effectiveness in many challenging industrial applications.

2. Tungsten

Tungsten is a steel-grey or silver-white refractory metal. Tungsten can be used as the base metal for an alloy or as a supporting element. Tungsten provides high hardness levels, a high resistance to heat and a high melting point. Tungsten is commonly used in Combustion liners, Turbine exhaust components, Aircraft cabin heaters, Transition Ducts & Industrial furnaces.

3. Stainless Steel

Stainless steel is an iron base alloy with a minimum of 10.5% or more of chromium as well as other metals like molybdenum and nickel. Stainless steel alloys are known for their resistance to corrosion and heat, which makes them ideal for use in the Aerospace, Automotive and Construction industries as well as specific parts like Pressure Vessels, Steam Turbines, Boilers and Piping systems.

4. Molybdenum

Molybdenum is a refractory metallic element that forms hard, stable carbides that enhance hardenability, strength, toughness and resistance to wear and corrosion. Molybdenum is frequently used in high-temperature alloys in steel, cast iron and super-alloys in the Military and Defence Industry, Semiconductor and Speciality Machine shops.

5. Nickel

Nickel is a naturally occurring silvery-white lustrous metal with a gold tinge. It is malleable, ductile and has superior strength and corrosion resistance. Nickel is frequently used in stainless steel and other alloys to make them stronger. Nickel alloys are used in Gas Turbines, Power Generation, Aerospace, Speciality Engineering and Electronics.

6. Tantalum

Tantalum is a shiny, silvery metal that is soft when pure. It is virtually resistant to corrosion due to an oxidised film on its surface. Tantalum is particularly useful in high-temperature applications in Aircraft Engines as well as Electronic Devices..

Other Factors That Affect An Alloy’s Heat Resistance

Every alloy has properties that make it react differently to other alloys when subjected to prolonged periods of heat.

Therefore, it is vital that you check the technical data, which describes the properties of the alloy, before deciding if it is ‘best fit’ for the specific operating environment.

Quite often the operating temperature is the first, and in some cases, the only data point that many people look at when making their choice of alloy. This is the wrong thing to do.

Heat resisting alloys should NOT be selected on the basis of maximum operating temperature alone, there are many other things to take into consideration. These include:

• The mechanical properties of the alloy at a specific temperature.
• The alloy’s resistance to oxidation.
• The alloy’s resistance to hot corrosion.
• The metallurgical stability of the material.

NeoNickel, the Supplier with a Proven Commitment to Quality.

At NeoNickel we provide the very best speciality alloys to companies throughout Europe. These companies demand high-quality alloys that remain stable, durable and reliable in the face of extreme temperatures.

We have been supplying businesses of all sizes in the aerospace, pharmaceutical, motorsport and thermal processing industries for many years. This experience and expertise allow us to give anyone looking for high-temperature alloys exactly what they need.

Vast Inventory of Heat Resistant Alloys

Please visit our thermal processing page for a list of associated Nickel and Stainless Steel alloys which are readily available from NeoNickel.

If you would like more information on our heat resistant alloys, or you wish to discuss choosing the right alloys for high-temperature service, please contact us and we’ll be happy to help!