Three Tungsten Carbide Thermal Spray Coatings and Their Uses

Tungsten Carbide Thermal Spray Powder

Tungsten carbide is used in many different applications from wedding rings to drill bits. As an integral part of the coating world, tungsten carbide coatings help many heavy industrial companies stay up and running longer. Not all tungsten carbide coatings are the same. There are many different chemical compositions of tungsten carbide thermal spray coatings with varying percentages of tungsten carbide and various metals to tailor the coating for different environments.

Tungsten carbide itself is a ceramic and therefore very hard, but brittle. With the addition of metals, like cobalt and nickel, you can increase the ductility of the overall coating and improve its performance. There are countless different formulas and compositions but the ones we apply the most are tungsten carbide cobalt, tungsten carbide nickel, and tungsten carbide cobalt chrome.

Tungsten Carbide Coating on a Ball Valve

Tungsten Carbide Cobalt

Tungsten Carbide Cobalt (88WC 12Co) is a wear coating that helps with sliding wear, abrasion and fretting resistance. As a rule, thermal spray coatings don’t typically handle impact or point loads well, but tungsten carbide cobalt does offer some impact wear resistance. Tungsten carbide cobalt is not very corrosion resistant therefore it is best in dry environments. One great application for this material is feed rolls; whether for paper, sheet metal, or other products.

Tungsten Carbide Nickel

Tungsten Carbide Nickel (90WC 10Ni) is also a wear coating but offers more corrosion resistance at a lower hardness. It also resists sliding wear, abrasion, and fretting. Since this tungsten carbide does not contain cobalt, it will not degrade in a radioactive environment. It works great for ball and gate valves among other applications.

Tungsten Carbide Cobalt Chrome

Tungsten Carbide Cobalt Chrome (86WC 10Co 4Cr) is a wear and corrosion resistant coating often used as a hard chrome plating alternative. It is harder than both tungsten carbide cobalt and tungsten carbide nickel, reaching up to the 70 HRC range, and excels in abrasion wear resistance and erosion fretting resistance. Tungsten carbide cobalt chrome is our most common material of the three and can also be applied with our High Velocity Air Fuel (HVAF) process creating a much more ductile and harder coating with superior corrosion resistance than HVOF applied tungsten carbide cobalt chrome.

HVAF Tungsten Carbide Coating for Large Roll


Different Tungsten Carbide Coatings, Different Applications

Each of these tungsten carbide coatings will provide wear resistance and extend the service life of your part. The key to the best solution is matching the right chemical composition to the right operating environment. For instance, some will do better than others in wet or corrosive environments. Temperature limitations are also another factor to watch for in coating selection. It is often best to work with a reliable thermal spray company to determine which one is right for you.