What requirements should thermal spray materials meet

       In principle, as long as it does not sublime below a certain temperature, solid materials that do not decompose can be used for spraying. Therefore, the materials that are widely used in spraying include not only metals, ceramics, but also plastic polymers and their composite materials, but there are some specific requirements for spraying materials:

(1) It should have certain thermal stability and will not sublimate or decompose in the high temperature of the flame.

(2) The coating material and the substrate should have similar thermal expansion coefficients to prevent the thermal expansion coefficient of the substrate from being too large due to rapid cooling during the coating formation process, and the uneven shrinkage will form a huge thermal stress, so that the coating is removed from the substrate. Peeling or cracking.

(3) The coating material should have good wettability with the substrate in the molten or semi-molten state to ensure good bonding performance between the coating and the substrate.

(4) When the coating material is powder, its size distribution should be relatively reasonable, and good fluidity can be obtained to obtain a good and uniform coating. When the coating material is a rod or wire, it should have a good The forming performance should be uniform and accurate.