Abstract
There have been a number of issues concerning the sliding characteristics of oil-impregnated sintered bearings caused at the temperature below zero. However, the relationship between bearing design parameters and tribological characteristics below zero has not been clarified yet. In this study, we experimentally investigated the coefficient of friction and separation degree between the oil-impregnated sintered bearing and the journal operating at below-freezing temperature. As a result, we found that apparent reduction in oil content within porous matrix due to the volume contraction of lubricant oil with decreasing temperature led to boundary or mixed lubrication condition, yielding a high and unstable coefficient of friction.
