Achievement

The creation of micro-scale surface depressions can change the lubrication status and help reduce friction and wear. Such an effect can be more significant for the contact of flat surfaces, such as in the case of the area interface between the surfaces of a mechanical die and workpicec. A diode pumped Nd:YVO4 picosecond laser of wavelength 532 nm was used to create an array of rectangular depressions in the surface of a D2 steel sample. The dimensions of each dimple were approximately 100 microns by 400 microns, with a 25 micron depth. The force required to pull a 2 mm wide strip of sheet steel across textured and non-textured samples was recorded along with known sliding speed and contact pressure. The results show a friction reduction of up to 40% with the textured sample when compared with the non-textured sample. This work provides a valuable means of reducing energy consumption in large scale mechanical systems via micro-scale feature control.