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Exhaust Ceramic Coating vs. Hot Arc Wire Spray: Performance Comparison

A common misconception is that Hot Arc Wire Spray & Zircotec’s proprietary plasma applied ceramic coatings provide the same outcome in terms of thermal barrier performance, this is not the case. This article will lift the lid on these processes, further explaining the differences between each method, and how these coatings are quite simply not the same.

Hot Arc Wire Thermal Spray (Wire Arc Spraying/ Twin Wire Arc Spray)


Wire Arc spraying is a process that typically requires two wires (where Aluminium, Zinc, Nickel alloys are commonly used – depending on application) fed into the pistol and electrically charged, forming an electric arc. The electric arc formed will then atomise the molten metal with compressed air, sprayed onto the substrate to form a coating. This form of thermal spraying will deposit the same material as the wire, which is commonly used for protecting from corrosion and wear, providing electrical conductivity and repairs.

Wire Spray Diagram


Diagram Plasma

Zircotec’s Plasma Applied Ceramic Coating


Although Zircotec’s proprietary plasma spray process sounds similar to other thermal spray methodologies, our plasma technology involves much higher temperatures to form a plasma arc, producing the atmosphere required for spraying. The ceramic particles are melted within a plasma flame that reaches approx. 10,000°C, and propelled towards the substrate at more than twice the speed of sound, deposited as molten and flattened droplets which adhere to the substrate as a coating. The composition of our proprietary ceramic powders heavily influences the outcome, setting our technology apart from others. Our plasma-sprayed coatings’ core function is its thermal barrier properties, which is utilised across various industries including automotive, aerospace, marine, and more. Aside from its extraordinary thermal properties, it can also protect coated substrates from corrosion and wear.

To summarise:



Although all these processes involve very high temperatures in a similar way, the outcome of the coatings are completely different, hence their core applications are also different. Apart from the application process, the composition of the coating material is also one of the determining factors of the coating quality, thickness, hardness, surface finish, and more – not all is suitable to be used as a thermal barrier coating applied onto exhaust systems.

Therefore in summary, comparing Hot Arc Wire coatings to Zircotec’s Plasma Spray is the equivalent to comparing apples to oranges.