Research on the Effect of Picosecond Laser Surface Texturing on Metal Surface Properties

The picosecond laser is used to form six different regular morphology microstructures on the surface of the stainless steel. These microstructures have micro-scale corrugated protrusions, and the surface of the protrusions is distributed with small micro-pits of nanometer scale. The elements composition of the processing area is basically the same as that of the substrate, and the content is also close. The content of C element increases and the content of Fe element decreases. The results show that the friction coefficient of the original surface is between 0.8 and 0.9, and the friction coefficient of the textured surface is reduced to between 0.1 and 0.2. The friction coefficient shows a stable change after climbing first, but the time when the textured surface reaches the steady state relative to the original surface is shorter. The wear scars of textured surface are wider than that of the original surface. It has better wear resistance when the rubbing direction is perpendicular to the texture. The wetting angle of the original surface is <90 degrees, and the surface is hydrophilic. The wetting angle of the textured surfaces are >90 degrees, most of which are 110 degrees similar to 120 degrees, and the surfaces are hydrophobicity. The surface friction coefficient is inversely related to the surface wetting angle.