Erosion and corrosion resistant coatings for refractory titanium alloys

摘要

The objective of the present paper is to present an overview of the resent developments on the problem of corrosion and erosion resistant coatings formation for improvement of operating properties of compressor blades from refractory titanium alloys. The choice of the composition, thickness, and deposition method of the coatings, formation and modification of equipment used for coating deposition in Russia are discussed. The effects of advanced coatings deposition regimes (ZrN, TiSiB, TiB_2, TiSiN, CeO_2, Y_2O_3, ZrO_2- Y_2O_3 etc.) on the chemical composition, structure, and properties of the refractory titanium alloys surface layer (the fatigue strength, the erosion resistance, the corrosion resistance, the oxidation resistance) are presented. It is shown that the coatings deposited by vacuum-plasma technology of high energies (ZrN, TiSiB) and chemical transport reactions in the liquid phase (CeO_2) have the best erosion and corrosion resistance. Incidentally, the fatigue strength of the titanium alloys with TiSiB and CeO_2 coatings is equal to one of the initial alloys without coatings. It is established that service properties of the titanium alloys with the resistant coatings can be improved using by complex technologies including the surface processing by intensive pulsed flaxes of energy ( high power pulsed ion beams, intensive pulsed electron beams, high power pulsed microwaves etc.). The latter is the most advanced method for the following applications: preparation of the surface before coating deposition; formation of the interface layers due to remelting of the deposited coating; improvement of the coating adhesion; ablation of the surface layer and coating damaged during operation.