Classification and development trend of thermal spraying materials

       There are many thermal spraying ceramic materials. Theoretically, the plasma spraying process can spray all solid engineering materials, but not all ceramic materials can be used as thermal spraying. Some ceramic materials can be used only after changes or special treatments. It cannot be used as a raw material for thermal spraying as a raw material for thermal spraying ceramic coatings. In addition to thermal spraying raw materials for thermal spraying, metal thermal spraying has some special circumstances.

  ⑴For ceramic materials that are easily oxidized and burned, such as carbides, graphite, diamonds, etc., they cannot be used immediately. They must be coated with heat-resistant and oxidation-resistant metals to become cermet composite powders before they can be used as heat. Spray raw materials.

  ⑵ Ceramics that have high vapor pressure and are easy to volatile and sublimate at high temperatures, such as magnesia, Ca2CO3, SiO2, etc., cannot be used as thermal spraying raw materials immediately.

  (3) For ceramic materials such as ZrO2, TiO2, which undergo crystal transformation when the temperature changes, modification treatment is usually carried out, or high-temperature phase ceramic materials are used.

 

What are the commonly used raw materials for thermal spraying

  In practice, we divide the thermal spraying raw materials into wire (bar) spraying raw materials, powder spraying raw materials, brazing raw materials and auxiliary materials according to their types.

  Thermal spray wire (bar) materials are divided into flame spray and arc spray wire (bar) materials.

  Thermal spray powder raw materials are divided into metal and alloy powder, self-fluxing alloy powder, abradable coating powder, ceramic powder, cermet powder, composite powder raw material.

  The key to brazing raw materials includes coating raw materials that need to be followed by diffusion heat treatment after thermal spraying.

  The key auxiliary materials include raw materials for sandblasting, masking raw materials and sealing raw materials.

The development trend of the thermal spray material market

  The key includes precision parts for the aerospace industry, automobiles, medical instruments and industrial production gas turbines. The application of thermal spray coatings in the biomedical and medical equipment industries will help improve their wear resistance and biocompatibility. It is also effective for denture implants.

  The continued expansion of the scope of application also includes ships, locomotives, tanks, helicopters and motorcycle gas turbines, which have also accelerated the prosperity of the thermal spray coating market. Taking full account of characteristics such as high temperature corrosion resistance, polymer and metal thermal spray coatings are usually used in powder form on industrial gas turbine blades.