Preparation And Properties Of Fly-Ash Composite Coating By Thermal Spraying On Q235

The mixed power is milled for 8 fours,which is used fly ash as main raw meterial,adding 10%Al,10%TiO₂,10%B₂O₃ Coatings is prepared respectively by thermochemical reaction, flame spraying and plasma spraying. XRD and SEM are used to characterize the composition and morphology of the ceramic coatings. The corrosion resistance,wear resistance,erosion and abrasi-on resistance of ceramic coatings are also tested.The results show that the coating prepared with composite powers by thermochemical reaction is feasible. The coating produces NiCr₂O₄,3CaO·Al₂O₃,Cr₂O₃,TiB₂. The acid, salty and oil medium corrosion of the thermo-chemical reaction coating increases by 21.06,2.10,2.16 times, respectively. The wear resistance increases by 2.55?5.00 times. The erosion wear and corrosion wear resistance increases by 2.16,1.32 times, respectively.The performance of coatings by flame spraying is better than that of thermo-chemical reac-tion. The coating pruduces Al₂O₃,TiB₂,3Al₂O₃·2SiO₂,3Ca₂SiO₄. The acid, salty and oil medium corrosion of the flame spray coating increases by 11.80,1.48,4.18 times,respect-tively. The wear resistance increases by 3.92?7.67 times. The erosion wear and corrosion wear resistance increases by 1.87?2.81,2.27?2.50 times, respectively.The performance of coatings by plasma spraying is better than that of flame spraying. The coating produces 3Al₂O₃·SiO₂,Al₂O₃,SiO₂,TiB₂. The acid, salty and oil medium corrosion of the plasma spraying coating increases by 33.64,3.47,22.3 times,respectively. The wear resistance increases by 6.10?16.11 times. The erosion wear and corrosion wear resistance increases by 3.78?6.04,4.79?8.16 times,respectively.