Materials with a cobalt base are alloyed with elements including iron, nickel, tungsten, and chromium to form cobalt alloys. They, like nickel-based alloys, are subjected to harsh conditions such as high acids and temperatures. While cobalt-based alloys are known for their corrosion resistance, they can be made even more durable by using a diffusion treatment.

beautifully formed cobalt alloys

Cobalt Alloy Basics

What Is It?

The metal cobalt (Co) has an atomic number of 27. Like iron and nickel, it is ferromagnetic by nature. Its density of 8.8g/m3 is comparable to that of nickel (8.91g/m3). However, it is heavier than iron. This substance is a high-temperature metal that melts at 1493°C.

Why Use Cobalt-based Alloys?

Cobalt-based alloys have several advantages. They have good mechanical characteristics in general. Likewise, they are heat, wear, and corrosion resistant, making them ideal for use in high-temperature applications like hot gas turbines. Cobalt also has a high resistance to sulfides, preventing the material from sulfidation.

What Is Its Chemical Composition?

This superalloy is a metal in which cobalt makes up the majority of the bulk composition. Most cobalt alloys have a cobalt-chromium base, with chromium functioning as a strengthening alloy. Adding molybdenum and/or tungsten can affect strengthening even more. Nickel is another common ingredient present in many cobalt-based alloys. Such an element is more heat-resistant than cobalt and is used to increase the temperature resistance of components.

end results of cobalt alloys forging

Hardening of Cobalt Alloys

Cobalt-based alloys have good strength. However, that isn’t adequate or practical in some applications. Other metal parts are sometimes required to operate at high temperatures while supporting great loads or being subjected to repeated stress. For these specific parts, diffusion coatings can improve hardness and wear resistance as well as improve corrosion resistance.Our certified hardening technique can greatly extend the life of your project. We also provide differential treatment for workpieces that are only partially treated. Schedule an appointment with our professionals at Ferralloy Inc. today!