In order to obtain higher energy efficiency and greater thrust, and heavy duty gas turbine engine turbine inlet temperature is as high as 1600 degrees above, only on the improvement of the performance of the materials and the improvement of structure design, has been unable to meet the rapid development of aviation engine and gas turbine industry needs, high temperature protective coating technology is essential. The fourth generation of high temperature protective coating, zirconia thermal barrier coating has been applied in some high temperature parts of aero-engine (guide vane, flame cylinder, heat insulation screen, etc.), and good results have been obtained.

Turbine is one of the three main engines -- boiler, steam turbine and generator in thermal power plant. Its body is composed of rotating part and fixed part. The rotating part is composed of an impeller, a spindle, a coupling and a blade. The fixed part consists of nozzle, cylinder, seal, baffle, fastener, bearing, etc.
In the process of thermal power generation, the thermal energy is converted into mechanical energy by the steam turbine. In the process of power generation, the efficiency of the power plant and the safety of the unit will be affected by the steam turbine. During the operation of the turbine generator set, after the steam enters the steam turbine, the impurities are carried by the steam into the steam turbine, which will form scaling and corrosion. Especially, the final blade runs under extremely harsh conditions, and bears the combined effects of high temperature, high pressure, centrifugal force, steam force, steam excitation force, corrosion and vibration, and water droplet erosion in wet steam area. The damage is even more significant. And with the increase of the load, due to the superheated steam carrying impurities, more and more serious corrosion, salt deposition turbine blades, the safe operation and efficiency of the unit has been more and more significant impact.
When the steam turbine is started, if the quality of superheated steam is not up to the required standard, if put into operation at this time, the salt will be carried into the steam turbine through the dissolution of steam, and gradually deposit on the turbine blades at all levels, so that the weight of the blades increases, and the output of the steam turbine will be affected. The salt imbalance will also cause uneven weight, which is likely to cause vibration. The corrosion of the blade under scaling will seriously damage the material and strength of the blade, which is easy to cause malignant accidents in the operation of the steam turbine.
Using supersonic spraying cermet coating can effectively improve the service life of turbine blades. Adopt repair welding, sandblasting, spraying transition layer, spraying layer, sealing agent, blade protection process. The combination of coating and blade surface has high strength, no shedding, coating life can reach more than four years, at the same time has reduced the use cost of 1/3 ~ 1/6, suitable for the blade in wet steam area and low load operating conditions of the final stage blade, new and old blade can be applied.