Tribological Properties of Lubricating Films on the Al-Si Alloy Surface via Laser Surface Texturing

Abstract

Dimpled textures were prepared by using a pulse solid laser on the surface of Al-Si alloy. The combination of laser surface texturing (LST) and MoS₂ solid lubricant as well as their tribological properties were investigated in this article. The obtained friction and wear data were critically analyzed to investigate how the parameters of texture influence the tribological performance of Al-Si alloy. Furthermore, morphological investigations of the transfer layers on the worn surfaces were performed and the wear mechanisms are discussed. The results show that the combination of LST and solid lubricant improves the tribological characteristics of Al-Si alloy. The friction coefficient of Al-Si alloy: steel friction pairs can be reduced to 0.15 under dry friction. The lubrication mechanism is attributed to a synergetic effect of providing solid lubricant and traps wear debris in the dimples. It was found that the optimum density of structure was 37% for excellent tribological properties.

KEY WORDS:

• Al-Si Alloy
• Laser Surface Texturing
• Solid Lubricant
• Tribological Properties

ACKNOWLEDGEMENTS

The authors gratefully acknowledge financial support of the National Basic Research Program of China (973 Program, Grant No. 2011CB706603) and the Innovative Group Foundation from The National Natural Science Foundation of China (NSFC) (Grant No. 50721062).

Review led by Victor Wong