What's this Carbide coating.

[charlieuk]

I have been looking for the best router bits for shaping polystyrene for a long while however I still yet to find a good solution that is not crazy priced. The best I have found so far is these burrs from the USA at $40 each and which are supposedly carbide coated however it would be great if they were a bit longer.There is one but in the USA also I have found but runs in at $600 each !

I have been looking every were to try and find out ho they do the spiky carbide coating but with no luck so as to possibly look into having something custom made possibly how ever no idea of cost or if it is even posable.

as it is only for cutting foam would it be posable to have some made with the spikes just in steel and then heat treated? I have no real idea but just looking for options other wise it will have to be a long flute to do a ruff out and change for a final pass with a burr.