Prediction of temperature rise in ball-on-disk contacts under electromechanical loading

Abstract

Traction motor bearings in electric vehicles fail prematurely due to electrical environments. Current flow through the bearings causes lubricant degradation due to a rise in the contact temperature. This study utilizes experimental and numerical methods to predict the expected temperature rise in ball-on-disk contacts subjected to electromechanical loading. Contact resistance and temperature rise are measured using a modified tribo device under static, dynamic, lubricated, and unlubricated conditions. The contact resistance depends on the magnitude of the current applied and contact conditions. A numerical model is proposed to predict the temperature rise at the electromechanical contact and is verified with measured temperatures. Prediction of contact temperatures due to electromechanical loads will assist in life estimation and development of appropriate lubricants.