Thermal barrier coatings (TBCs) on the superalloy turbine blades can lower the temperature of metallic substrate by 100-300 ℃,allowing an increase in the turbine entry temperature.These coatings are generally fabricated by plasma spray techniques in industrial practice.However,the recently developed detonation gun spray process offers a competing technology to deposit TBCs.Compared with the TBCs produced by conventional plasma spray processes,the detonation gun sprayed TBCs have denser microstructure,improved adhesion to the substrate due to a high particle velocity,and lower energy cost.