Powders for spray-fusing and spraying

Powders for spray-fusing

1, Nickel-based self-fluxing alloy powder mainly refers to NiCrBSi alloy. This kind of alloy with low melting point, good self-fluxing nature, anti-wearance, anti-corrosion, heat resistance and oxidation resistance. It is the earliest and most widely used self-fluxing alloy powder.

2, Iron-based self-fluxing alloy powder is more widely used than cobalt, nickel-based self-fluxing alloy powder. It has a certain anti-wearance and heat resistance, although the spay fusing ability and self-fluxing is not as good as nickel-based and cobalt-based alloy, the operation is also difficult to grasp, but its main advantage is low price.

3, Cobalt-based self-fluxing alloy powder is usually developed based on CoCrW alloy, it has better thermal strength and resistance to high temperature oxidation than nickel based alloy powder, but also has good property of anti-corrosion and anti-wear. But the price is expensive.

4, Nickel-based tungsten carbide alloy powder mainly refers to add high hardness wear-resistant material WC based on the nickel-based self-fluxing alloy, in order to make it has better anti-wearance property.

Spraying powders

It usually divided into composite self-bonding powders and working powders.

Self-bonding powder means that the powder is heated to a certain temperature, the powder will be self-reheat, thereby increasing the powder temperature, so the powder and substrate can form a micro diffusion, to achieve a solid combination, and provide active coating for working powder coating. After spraying Self-bonding powder, the combination of coating and the substrate can up to 2-5kg/mm³ (20-50mpa) and even more. If by explosion spray or HVOF, can reach to 10kg/mm³ and more. The combination of the coating and substrate belongs to mechanical combination, because of temperature control of substrate surface during the process of spraying should not exceed 250 ℃, so the workpiece will not be deformed.

Working layer powder is designed to meet the needs of a variety of working conditions, not necessarily with self-fluxing, deposition efficiency is also improved. According to its texture composition can be divided into nickel based, iron based, chromium based and cermet powders.