The effect of laser texturing of steel surfaces and speed-load parameters on the transition of lubrication regime from boundary to hydrodynamic

Laser surface texturing (LST) is tin emerging, effective method for improving the tribological performance of friction units lubricated with oil. In LST technology, a pulsating laser beam is used to create thousands of arranged microdimples on a surface by a material ablation process. These dimples generate hydrodynamic pressure between oil-lubricated parallel sliding surfaces. The impact of LST on lubricating-regime transitions was investigated in this study. Tribological experiments were carried out on pin-on-disk test apparatus at sliding speeds that ranged front 0.15 to 0.75 m/s and nominal contact pressures that ranged front 0.16 to 1.6 MPa. Two types of oil with different viscosities (54.8 cSt and 124.7 cSt at 40degreesC) were evaluated its lubricants. Electrical resistance between flat-pin and laser-textured disks was used to determine the operating lubrication regime. The test results showed that laser texturing expanded the range of speed-load parameters for hydrodynamic lubrication. LST also reduced the measured friction coefficients of contacts that operated tinder the hydrodynamic regime. The beneficial,effects of laser surface texturing tire more pronounced tit higher speeds and loads and with higher viscosity oil.