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

摘要

近年，各種機械の省エネルギー化において摩擦損失の削減が求められており，潤滑部では油の低粘度化がその対策として有効とされている.一般に，低粘度油の使用は流体潤滑域での低摩擦化を可能とするが、その一方でしゅう動部の一部を比較的摩擦係数の高い境界潤滑域に移してしまう.したがって，低粘度化における潤滑システム全体での摩擦損失削減を実現するには，境界潤滑域での低摩擦化が必要とされる.%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 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.