Modeling on contact fatigue under starved lubrication condition

This study develops a model for the description of surface breaking crack initiation, under starved lubrication condition. Varying from fully flooded to severely starved lubrication condition, impacts of important factors, including surface roughness, contact pressure, and lubricant viscosity, on fatigue life are examined. Surprisingly and interestingly, it is found a lower lubricant viscosity elongates fatigue life when severe starvation occurs, which is opposite to the EHL rule under fully flooded lubrication condition, stating higher viscosity leads to thicker lubrication film and improved fatigue life. However, it is in line with the experimental observation (Cann in Tribol Trans 42(4):867-873, 1999), where film thickness was shown to increase when moving from high viscosity base oil to a lower one under starvation condition.

Automated summary

This study found that lower lubricant viscosity can extend fatigue life under severe starvation condition, contradicting the EHL rule under fully flooded lubrication condition. Additionally, experimental observation supports that under starvation condition, film thickness increases when shifting from high viscosity base oil to a lower one.