Y. Gao, L. T. An, Dalian Maritime University, Dalian, China
Alumina coatings was prepared by the plasma spray with powder injected at different location i.e., internal axial injected close up the cathode before the arc root point, internal powder inject to the nozzle inside behind the arc root point and at exit of the nozzle plasma torch. The result shows that the deposition rate increasing from 15% to 50% with powder injecting closed to the cathode at arc current of 200A and voltage of 60V with Ar-H2 plasma gases. The microstructure of the coatings and phase transition fromδoriginal powder to γ phase main in coatings was also investigated by X-ray diffraction.
Summary: Alumina coatings was prepared by the plasma spray with powder injected at different location i.e., internal axial injected close up the cathode before the arc root point, internal powder inject to the nozzle inside behind the arc root point and at exit of the nozzle plasma torch. The result shows that the deposition rate increasing from 15% to 50% with powder injecting closed to the cathode at arc current of 200A and voltage of 60V with Ar-H2 plasma gases. The microstructure of the coatings and phase transition fromäoriginal powder to ã phase main in coatings was also investigated by X-ray diffraction.
