Effect of loading on the friction and interface microstructure of lubricated steel tribopairs

摘要

In this study, the tribological behavior and interfacial evolution of GCr15/Mild steel tribopairs lubricated by inorganic sodium metaphosphate was investigated under different applied loads at 800 degrees C. The results show that sodium metaphosphate lubricates the contact effectively at the load ranging from 5 to 30 N, with higher loads causing increased friction and wear. A layer of glassy phosphate film formed between the contacts is responsible for the improved tribological performance. FIB/TEM and XRD analysis reveals that the phosphate film was mainly composed of amorphous Na-Fe orthophosphate matrix filled up with fine oxide wear debris.