MoP・ZnDTP併用条件における境界潤滑特性とその潤滑機構に関する研究

抄録

This paper describes the boundary lubrication property in the lubricant containing molybdenum phosphate (MoP) and zinc dialkyldithiophosphate (ZnDTP). To study this, spinning type friction test was conducted, and the chemical reaction film formed after the test was analyzed by energy-dispersive X-ray analysis and Raman spectroscopy. The results showed that the friction coefficient in the combined condition of MoP and ZnDTP was lower than that in the condition using molybdenum dithiocarbamate. In addition, surface analysis results revealed that the chemical reaction film comprising molybdenum disulfide, phosphorus film and sulfide film was formed on the friction surface after the test, with formed molybdenum disulfide showed the layer film structure. It was also shown that the friction coefficient depends on the concentration of ZnDTP, with the condition of sulfur concentration of 300 ppm having the lowest coefficient in this test conditions. Moreover, the concentration of sulfur in the chemical reaction film increased with increasing the concentration of ZnDTP, that implies the friction properties relates with the amount of sulfide film such as iron sulfide.