Thermo-mechanical analysis of hydrogen permeation in lubricated rubbing contacts

Abstract

Exploring the fundamental mechanisms of hydrogen generation from a lubricated rubbing contact is a critical step to mitigate premature failure of mechanical elements. This work employs an in-situ hydrogen uptake technique and molecular dynamics simulations to study the thermo-mechanical effects on the hydrogen generation in lubricated contacts. The hydrogen uptake is measured on AISI 52100 bearing steel at temperature of 27 ◦C and 85 ◦C under applied pressure of 140 kPa and 350 kPa. Experimental measurements are modeled through atomic simulations using the reactive force field potential. The hydrogen generation associated with the Poly Alpha Olefin decomposition is studied through calculating the pair distribution function. Findings demonstrate enhancing hydrocarbon decomposition with increasing temperature and pressure, while a critical pressure is required for the decomposition process at the ambient temperature. The critical pressure for lubricant degradation is reduced with increasing the temperature. This study highlights the incorporation of thermo-mechanical effects on the hydrogen generation for the design and development of lubricated rubbing contacts.