Preparation of Superhydrophobic 35CrMo Surface and Its Tribological Properties in Water Lubrication

The process of oil exploitation is often accompanied by the generation of the corrosive gases, metal particles and minerals, which results in very serious corrosion and wear of petroleum machinery and equipment, which can be greatly reduced by modification of the surface properties of the materials. According to the theory of molecular interaction, the friction effect of a rough surface is better than that of a smooth surface, while fabrication of surfaces with appropriate roughness may reduce the friction. We present the construction of a grooved texture on the surface of 35CrMo using a nano-pulse laser. We found that some micro-/nano-structures were created on the surface, and that a superhydrophobic surface with a water contact angle of 156 degrees and a sliding angle of less than 10 degrees was obtained. Groove textures of different depths produced by using various laser energy densities, the friction coefficient of the superhydrophobic samples was significantly reduced from 0.55 to 0.28 after laser surface texturing under water lubrication conditions. This shows the improvement of the tribological properties.