Abstract
Factors influencing friction reduction with MODTP(molybdenum dialkyl dithiophosphate) lubricant were investigated through a frictioning experiment using two-cylinder edge surface frictioning tester and XPS surface analysis. The friction reduction effect gained with MoDTP lubricant appeared to be largely attributable to MoS$_2$ formation on the frictioning interface. Under N$_2$ atmosphere, Mo diffused into the metal substrate, easily escaping from MoS$_2$ so the friction reduction effect from MoDTP was not gained. However, when an oxide surface film was preliminary prepared on frictioning surface, this Mo diffusion to metal substrate from MoS$_2$ was effectively inhibited. Then desired lubulication effect of MoDTP was gained even under N$_2$atmosphere. As such, the existence of a surface oxide film on the frictioning surface was concluded to be of essential importance in order to gain a lubrcating effect with MoDTP.
Molybdenum dialkyl dithiophosphate(MoDTP) 마찰특성을 이원통 마찰시험기에 의한 마찰실험 및 X-선광전자분광분석기를 이용하여 마찰표면을 분석함으로써 MoDTP의 마찰감소 작용에 대해 고찰하였다 MoDTP의 마찰감소작용은 마찰표면에 생성하는 MoS$_2$에 의존하였다. 몰리브덴(Mo)이 용이하게 금속내부로 확산하는 질소분위기 중에서는 MoDTP의 마찰감소 특성은 나타나지 않았으며, 금속표면에 산화피막이 존재할 때 MoDTP의 마찰감소작용이 잘 나타남을 알 수 있었다