Thermal spray high temperature oxidation resistant coating

       Industrial alloys or metals are oxidized at high temperatures to form TGO. With the progress of the oxidation reaction, the metal elements are continuously consumed, which eventually causes the failure of the material, which shortens the service life of the workpiece and affects the product quality and work efficiency.



In the field of thermal spraying, MCrAlY is generally used (M generally chooses Ni, because of its thermal stress relaxation ability and good ductility in the longitudinal and transverse directions; Co is also selected because of its better oxidation resistance and lower thermal expansion coefficient, However, the powder of this component is expensive; there are also Fe-based ones, which have stronger plasticity than the former two, have anti-vulcanization ability and low procurement cost, but are not suitable for preparing coatings on nickel-based and cobalt-based substrates. At present, M Ni+CO is the trend) After preparing the transition layer, TBC is used as the surface layer to achieve the purpose of anti-oxidation in a high temperature environment of 1100 degrees Celsius. Antioxidant coatings at temperatures of 540-900 degrees Celsius can also be prepared with Ni/Al+Cr2O3 or Al2O3.



It is recommended to use supersonic flame equipment to prepare high temperature resistant coatings. The MCrAlY transition coating has higher bonding strength, dense coating and less oxide inclusions, which is conducive to the formation of a continuous and dense oxide protective layer and inhibits element diffusion.