不同滑滾比下點接觸之薄膜潤滑狀態

Abstract

本研究初步先修改現有試驗機，使其足以符合在彈液動潤滑條件下量測摩擦扭力的需要。接著藉量測點接觸相同表面速度和但不同滑滾比的摩擦扭力、不同表面速度但相同滑滾比的摩擦扭力，以及觀察其磨耗情形，分析滑滾比及表面速度和對潤滑情形的影響。結果發現滑滾比及表面速度和的增加均會造成摩擦力下降的趨勢，然而由其破壞條件及相同條件的表面狀況觀之，則發現滑滾比及表面速度和的增加均使油膜承載力降低。 藉過去的相關研究及理論，可推斷剪率的增加，超越了油膜層流所產生的極限剪應力，促使油膜分層，發生不連續的速度梯度，降低承載力，進而產生表面破壞。

In order to measure the frictional torque under elastohydrodynamic lubrication condition, this study is to modify a tribological tester which we already have. Then using this tester, the effect of the sum of surface speed and slip ratio on the friction coefficient and load carrying capacity of the oil films generated between point contact can be evaluated by the wear conditions of the tested specimens under elastohydrodynamic conditions. The experimental results show that the increase in sliding-rolling ratio and the sum of surface speed not only caused the friction coefficient between specimens to decrease, but also caused the specimens to be worn more easily. This result means that the load carrying capacity of the oil film decreases as the sliding-rolling ratio and the sum of surface speed between two disc specimens in elliptic contact increases.