Depending on the formulation of the coating, HVOF Tungsten Carbide Coatings have the capability of offering multiple property applications. Because of this, these coatings specifically can be used for a wider, more diverse range of coating applications.

Having a multi-application coating really changes the game and adds a level of versatility but… how long does the HVOF Tungsten Carbide Coating last? And what things do you need to look out for in maintaining the condition of the coating?

What Is A HVOF Coating?

HVOF stands for High Velocity Oxygen Fuel and it is a thermal spray coating process that is used to either improve or restore the surface of a component. It’s a technique of surface engineering and extends the life of the component by increasing its resistance to wear, corrosion, and erosion.

Mixing fluid fuel and oxygen is how HVOF spraying works – the combination of fuel and oxygen is fed into a combustion chamber and ignited. As a result, the gas has an incredibly high temperature and a high pressure which is ejected through a nozzle at a supersonic speed.

The powder of the coating substance, like Tungsten Carbide for instance, is introduced to the high velocity gas stream where it is then directed at the surface getting coated.

Tungsten Carbide Coatings

Tungsten carbide is usually a grey, fine powder in its most basic form. It can, however, be formed and pressed to create jewellery, tools, or industrial machinery components.

Tungsten carbide itself is more of a brittle ceramic but when it is combined with a small portion of metallic powder (Ni, Cr, or Co), it becomes a carbide coating. As a carbide coating, Tungsten carbide has a strong resistance to abrasion, wear, and erosion.

Can Anything Affect The Durability of HVOF Tungsten Carbide Coatings?

One thing that can have an affect on the durability of a HVOF Tungsten Carbide coating is the fatigue life of the part that is being coated. No matter which process of thermal spraying you use, the coating that is applied can significantly reduce the fatigue life of the component. Especially when compared to a non-coated component.

The fatigue life of HVOF tungsten carbide coatings has been tested to relate with the level of compressive residual stress the coating is introduced to. When the level of compressive residual stress increases, the fatigue life of the coating did, also.

Benefits of HVOF Tungsten Carbide Coatings

When tungsten carbide coatings are applied with HVOF spraying, the particles flatten and immediately bond with the substrate. The coating only builds in strength as more and more HVOF coating particles hit the workpiece.

Using HVOF thermal spray for tungsten carbide coatings results in a coating with a strong bond strength, high density, excellent resistance to corrosion, erosion, and wear, and low residual stress. Furthermore, HVOF thermal spray processes are more flexible when it comes to customisable coatings.

The wear resistance and the strength all depend on the volume and grain size of the particles, plus the type of metallic binder. Therefore, you can adapt the hardness as well as those other properties of the carbide coating to meet the specific needs of each client we speak to.

These are some of the other benefits of HVOF Coatings:

  • There’s a lower oxide content because of the decreased in-flight exposure time.
  • Because of the low residual stress, the coating is thicker.
  • The higher impact velocities and the small powder sizes create a surface that is smoother as the spray coating is applied.
  • A reduced time at high temperatures causes increased retention of the powder chemistry.

Alphatek: Your Thermal Spray Coating Specialists

At Alphatek, HVOF tungsten carbide thermal spray coating is one of our most popular thermal sprays applied for wear-resistant surface treatments. It may even be our most frequently used.

Over the years and by working closely with our customers, Alphatek has developed products and services that deliver only the best of the best. That includes value, efficiency, and quality. Delivering the best the first time, every time, with a service that is stress-free – suitable for everyone.

We have both the capabilities and the facility to perform services for a complex range of parts, whether they’re small individual components or larger drums like rails or tanks.

Contact Us Today

Our experience here is unparalleled.

We have a combined 100+ years of cumulative coating experience in house. You can be confident that we’ll deliver.

Look no further than us for your metal spraying and thermal spray coating specialists. Ring 01706 821 021 to call one of our team and speak to them directly or just send us a quick email at postbox@alphatek.co.uk.