Estimation of the Molecular Junction Temperatures in Four-Ball Contacts by Chemical Reaction Rate Studies

A super-refined paraffinic mineral oil has been used to study the chemical reactions under boundary conditions in a four-ball wear tester. By quantatively analyzing the wear debris generated, chemical reaction rate data used to correlate between dynamic wear tests and static, externally controlled temperature runs. The reaction temperature at the wear junction has been estimated to be 351°C for 40kg load, 600 rpm, 75°C bulk oil temperature. This temperature is higher than the Blok-Archard flash temperatures calculated under the same conditions.