What is Plasma Spraying?

If you are a regular visitor to the website, or have even just visited our “processes” page one time, you may be aware that we apply our thermal barrier application via a plasma-spray process.
Which sounds pretty cool, but I was made aware yesterday that not everyone knows what that actually means and why it is a benefit to the coating process.

First of all, what you need to know is that plasma-spraying is a popular form of thermal spraying.

Thermal Spraying techniques are coating processes in which melted (or heated) materials are sprayed onto a surface. The “feedstock” or coating precursor is heated by electrical or chemical means. The coating materials are fed in powder form, heated to a molten or semi molten state and accelerated towards substrates in the form of micrometer-size particles. Combustion or electrical arc discharge is usually used as the source of energy for energy for thermal spraying. Resulting coatings are made by the accumulation of numerous sprayed particles. The surface may not heat up significantly, allowing the coating of flammable substances.

In our plasma-spraying process, we use a modified system and proprietary spray parameters that originate from our own R&D programme and are unique to Zircotec. The material to be deposited, a powder, is introduced into the plasma jet, emanating from a plasma torch. In the jet, where the temperature is in the order of 10,000°C, the powder is entirely melted and propelled towards the substrate. There, the molten droplets flatten, rapidly solidify and form a deposit that remains adherent to the substrate as coatings; it is in effect “welded” to the substrate.

Our processes have been refined by Zircotec, from the Nuclear Industry, and use highly advanced technologies and procedures. But the basis for our plasma-spraying remains the same, with a few extra developments we’ve learned along the way.

There are a range of parameters that can affect the results of plasma-spraying i.e feed-rate, gas composition, flow rate etc. The Zircotec parameters have been developed over years of Engineering and development and are tightly controlled by our specialist staff, providing complete control over the quality of the final product.

By controlling these parameters, we are also able to control material properties, to suit bespoke applications, making each thermal barrier we apply the best solution we offer for your specific need.