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Thermal spray coatings, explained
Melt a feedstock, drive it onto the surface, let it bond. That simple idea opens up materials plating cannot touch.
The basic idea
Thermal spray melts a feedstock — a wire or a powder — and drives the molten particles onto the surface of a part, where they flatten, cool and bond mechanically to build a coating. Because the coating is built from melted material rather than deposited out of a chemical solution, it can be made from things you cannot electroplate: hard metals, carbides and ceramics.
That is the whole advantage in one sentence. Plating gives you chromium; thermal spray gives you a menu.
The three we run
Flame spray
A combustion flame melts the feedstock. A versatile, well-established process for building up and coating a wide range of components.
Plasma flame spray
A plasma torch reaches far higher temperatures, which lets it spray refractory materials and hard ceramics that a combustion flame cannot melt. We apply plasma spray to AMS 2437, as revised.
Twin wire arc spray
An electric arc between two wires melts them, and compressed air atomises the melt onto the part. Efficient for laying down metal coatings and rebuilding worn surfaces.
When spray beats plating
Reach for thermal spray when the duty needs something chrome cannot give. Heavy abrasion wants tungsten carbide, which goes harder than chrome. An electrically insulating or ceramic surface wants aluminum oxide or chrome oxide, which are not platable at all. And long components can be sprayed where they would exceed a practical plating setup — sprayed parts here run up to 6" × 120".
When the part wants a dense, fine-finishing, low-friction surface — a hydraulic rod, a seal journal — hard chrome is usually still the better answer. The two are complementary, not rivals, which is why we run both.
It still gets ground to size
A sprayed coating, like a plated one, is deposited a little heavy and then brought to final dimension by precision grinding — in the same building. So a sprayed rebuild leaves measured back to print, not approximately restored.
Not sure if your part wants spray or chrome?
That is exactly the call we make every day. Send it over.
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Send us the part
A drawing, a photograph, or just a description of how it failed. We will tell you what we would do with it.