ENERGETIC CONDITIONS OF MAXIMISING TEMPERATUREAND ENERGY DENSITY IN THE ENVIRONMENT OF FRICTIONCONTACT OF SOLIDS

Abstract

The paper is intended to determine maximum temperatures in the friction zone of solids. An original model ofthermal processes in a miniature test object – environment of a selected contact of asperities – is proposed. Itsvolume is limited to an area where energy dissipation and wear take place. The discussion is based on an energybalance including temperature variations within the object. An original method of establishing the maximumvalue of the so-called flash temperature on the basis of an experiment addressing the thermodynamic natureof friction is proposed. A method of determining average density of energy dissipated in a tested volume isspecified as well. An analytical description of elementary friction includes physical properties of a material:density, specific heat, hardness; parameters characterising friction and wear, such as coefficient of friction,coefficient of wear, nominal unit pressure, specific work of wear, unit work of mechanical dissipation,temperature of friction surface, temperature of the immediate environment of surface asperities contact,mass of energy dissipation area, mass wear, and structure of the energy balance. The proposed description offriction within a contact of surface asperities encompasses analytical dependences that relate all the physicalquantities accepted as characteristics of an object and the process inside it to one another. A quantitativeevaluation of the maximum temperature and density of dissipated energy is undertaken for a selected instanceof tribological testing.