The Tribological Behavior of Cast Iron by Laser Surface Texturing under Oil-Lubricated Initial Line Contact for Rotary Compressor

The tribological behaviors of cast iron by laser surface texturing were experimentally compared with the behavior of untextured by unidirectional rotary sliding friction and wear tests under oil-lubricated initial line contact. The friction coefficient and temperature rise were analyzed with the increasing load applied by block-on-ring tests. In addition, the wear loss and wear mechanism were also investigated through the surface topographies analysis. The results showed that the tribological improvement strongly depended on the contact form. For the oil-lubricated initial line contact in this work, the textured surface showed a better frictional advantage with a lower friction coefficient and lower temperature rise. The hydrodynamic effect enhanced the load-carrying capacity of the oil film and increased the film thickness. The friction coefficients were 11~64% lower than those on the untextured one. Meanwhile, the textured surface deteriorated the wear behavior due to the coupling effect between the micro-cutting effect of the texture edges and the material deformations of the counter surface. The material loss induced by abrasive wear and fatigue wear was the dominant wear mechanism. Namely, the laser surface texturing improved the friction properties but reduced the wear resistance.