The selection of Spray welding material

Spray and Fusing is to reheat preheated self-fluxing alloy powder coating up to 1000~1300℃,melting the particle and slagging coming up to the surface of the coatings, and the generated boride and silicide will be diffused in the coatings, and making the inter-particle and the substrate good Bonding strength. The final deposit is compact metallurgy bonded coatings formed with metal crystallized structure and substrate, the bonding strength of which is about 400MPa, and it is mirror surface, which has better shock resistance, wear resistance and anti-corrosion.

Self-fluxing alloy powders mainly are based on nickel, cobalt and iron, adding moderate boron and silicon, as deoxidizing slag-making welding flux, and it can lower melting point at the same time. It's suitable to re-melt the coatings by acetylene-oxygen flame.

There are many kinds of self-fluxing alloy powders. Nickel-based alloy powder has strong corrosion resistance, abrasion resistance and oxidation resistant under 650 °C. Cobalt based alloy powder has good red hardness and it can maintain good wear resistance and corrosion resistance at Max 700 ℃. The wear resistance of iron-based alloy powder is better than nickel and coablt.

Spray and Fusing can’t be used for below situations:

(1) Substrate materials’ melting point lower than alloy powders, such as aluminum and its alloys, magnesium and its alloys, brass, bronze, etc.

(2) Thin shaft or thin plate which is not allowed to be deformed;

(3) High requirement workpiece of original design, and the microstructure is not allowed to be changed;