How much hardness of tungsten carbide spraying layer is the tungsten carbide spraying thickness

       What is the hardness of the tungsten carbide spray coating and what is the thickness of the tungsten carbide spray

The hardness of the tungsten carbide coating is generally above HV1200, and the thickness of the sprayed tungsten carbide coating is 0.1-0.5mm.

The hardness of the coating after tungsten carbide spraying has no big correlation with the thickness, but it is directly related to the length of time it stays in the high temperature range. The highest hardness of the coating of tungsten carbide spraying is HRC65

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So what is going on with many manufacturers saying that they can achieve HRC72?

That is micro hardness!

Figure (1) Special equipment for testing the hardness of tungsten carbide coating, the hardness of tungsten carbide coating is HV Vickers hardness

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I don’t know if the coating material in spraying leaves the spray gun and reaches the surface of the substrate. The longer it takes, the softer it is. The shorter the time, the harder it is. Is it too close?

Reply

Tungsten carbide is only mechanically mixed with self-fluxing alloy powder, and it does not melt itself. The micro-hardness is the hardness of tungsten carbide itself 72. The longer the time to leave the spray gun to the surface of the substrate, the longer the distance between the spray gun and the workpiece, the lower the powder kinetic energy, and the shorter the time, the lower the powder temperature of the self-fluxing alloy powder. , Can not reach the semi-melted state, the adhesion will be reduced, and it is easy to peel off. What I mean by "the time to stay in the high temperature range" is the remelting time as short as possible, not the time for the material to leave the spray gun and reach the surface of the substrate

Figure (2) The thickness of the tungsten carbide coating is measured by an eddy current thickness detector. This figure shows a company testing the thickness of the tungsten carbide coating on the inner wall of the pipeline.

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Is HRC72 the highest microhardness of tungsten carbide? The actual hardness of the actual coating is around HRC65. Is there any coating material that is harder than tungsten carbide? What is it? What is the microscopic hardness? What is the actual hardness? The hardened layer is actually tungsten carbide particles, which has not melted, but is actually wrapped by other self-dissolving alloy powders. Just like the jelly we eat, grapes are still grapes, but they are fused together by edible glue. I understand that. ? Looking forward to reply

Reply

Your understanding is completely correct! As far as I know, there is no coating material harder than tungsten carbide.