Experimental observations of brake and clutch systems reveal that thermal localisations within contact area are source of increased wear and friction induced emission, judder, plastic deformation, and cracks. Non-uniform contact areas come from wear and thermomechanical phenomenon such as hot bands and several type of hot spots on sliding bodies. The aim of the study is to predict macroscopic evolving thermal localisation process with stability and transient analysis. The develop strategy consist first in classifying thermal localisation and associated phenomenon. As a classical way of thermoelastic instabilities, a stability numerical approach has been developed to predict occurrence of unstable mode of the system. Even if results of stability numerical approach are close to theorical approach for simple 2D geometry, it remains strong assumptions in such modelling: full contact, material elastic behaviour, etc…. Another approach is to consider transient effects with time-domain numerical model which can take account more complex mechanical behaviour and mechanisms. Numerical simulation may predict thermal localisations, which depend on brake and clutch geometry, system induces contact pressure and type of thermomechanical loading: more or less straight hot bands, on surface or depth phenomenon, hot spots, etc…. Associated contact level of stress and strains may be so quantified and used for thermomechanical-tribological coupling studies in contact areas.

University of Lille: Dr. Jean-François Brunel, Dr. Philippe Dufrénoy, Mr. Valentin Bruant