Influence of Surface Texture and Surface Film on Cavitation Erosion Characteristics of Ti6Al4V Alloy

Abstract:

Surface texture manufacturing to Ti6Al4V alloy by a laser surface modification method and self-assembled monolayers (SAMs) prepared on the texturing surface by a self-assembled method were conducted in order to study the effect of surface texture and surface film on the characteristics of cavitation erosion resistance of materials. The surface properties of the specimens were characterized by measurement of contact angles. Cavitation erosion mechanism of the specimens was analyzed by measurement of cavitation erosion characteristics and topography observation before and after cavitation erosion occurrence. The results indicate that cavitation erosion resistance of Ti6Al4V specimens are significantly enhanced by laser texture manufacturing. The cavitation erosion resistance is further improved by self-assembled monolayers prepared on texturing surface because of the hydrophobicity. The cavitation erosion resistance of specimens with grid texture is bigger than that of specimens with line texture because the former possesses higher hardness, higher hardness gradient and even protrudent hard point distribution. The cavitation erosion resistance of specimens with FOTS SAMs for both grid texture and line texture increases with space increasing. The cavitation erosion resistance of specimens without FOTS SAMs for both two textures decreases with space increasing

Key words:titanium alloy; cavitation erosion; laser manufacturing; surface texture; self-assembled monolayers