Study of the Friction and Wear Behavior of Laser Micro-Precisely Treated Alloy Cast Iron under Lubrication

Alloy cast iron specimens were treated making use of laser micro-precision technology. The friction and wear behavior of the modified samples was investigated using an SRV test rig. The microstructure and worn surface morphology of the treated samples were observed using a scanning electron microscope. The chemical states of the typical elements on the worn surface of the laser micro-precision treated alloy cast iron specimens were determined by means of X-ray photoelectron spectroscopy. It was found that the treated alloy cast iron specimens had improved surface topography and significantly increase hardness and wear resistance. At the same time, the wear of the treated alloy cast iron samples was greatly decreased under the lubrication of liquid paraffin containing various extreme pressure and antiwear additives. This was because the specific surface morphology of the treated samples helped to store the lubricating oil and make full use of the friction-reducing and antiwear ability of the lubricant. The load-carrying capacity and antiwear ability of the tested base oil and additives were ranked as ZDDP>TCP>SO>liquid paraffin. The reason lay in that ZDDP was able to form a lubricating and protective film on the alloy cast iron surface by way of physico-chemical adsorption and tribochemical reaction, which contributed to greatly increasing the load-carrying capacity and antiwear ability of the lubricant.