RESEARCH ON WEAR RESISTANCE COATING OF AIRCRAFT TITANIUM ALLOY PARTS BY COLD SPRAYING TECHNOLOGY

Abstract

Titanium alloys are the main structural material of aerospace system component, about 75 % of titanium and titanium alloys are used in the aerospace industry, which have the advantages of low density, high specific strength and excellent corrosion resistance, However, its low wear resistance limits the further application of titanium alloy. Therefore, it is of great significance to the surface protection of titanium alloy. Surface coating technology can solve the problems of titanium alloy wear. Currently, there are many coating technologies to solve the problems of wear and corrosion, including the cold spraying(CS), high velocity oxy-fuel(HVOF), the thermo-chemical treatment, the gas phase deposition, the laser melted; the plasma spray coating, the double-plasma surface alloying technology, arc spray, etc, However, when thermal spraying is used to prepare anti-titanium fire coating, the tip of the blade is prone to overheating, thus affecting the performance of the blade. But cold spraying technology is due to the preparation of titanium alloy protective coating in solid state, and the coating has high bonding strength and good impact toughness, furthermore, it can deposit almost any powder materials, such as pure metals, including aluminum(Al), magnesium(Mg), titanium(Ti), nickel(Ni), cobalt(Co)，niobium(Nb), tantalum(Ta), Copper(Cu), tungsten(W), etc; nonmetal such as ceramic, etc; Metallic alloys; composite coating, including Al-Zn, Ti-Al, Ni-Al, Al-Mg, Al-SiC, Al-Al2O3, Ti-Ti6Al4V-Al2O3, Ni-Zn, Ni-cBN, Ni-Zn-Al2O3, Ti-Ta, Al-Mg17Al12, Al-FeSiBNbCu, WC-Co, Cr3C2-NiCr, etc. It can also directly sprayed mixed powder to produce wear resistant coatings, hence, it is widely used. At present, cold-sprayed titanium alloy materials are mainly used in the field of substrate protection and repair, and the field of cold-sprayed titanium alloy additive manufacturing that has appeared in recent years is still in the stage of process and basic theoretical exploration. In order to better understand the latest status of cold spray coating of titanium alloy, in this paper, the wear resistance coating on aircraft titanium alloy parts by cold spraying technology was reviewed, produce wear resistance coating directly by cold spraying technology was analyzed.