TIME FACTOR OF MECHANICAL LOAD IMPACT ON THERMAL RESISTANCE IN CONTACTING METAL SURFACES
The process of formation of contact thermal resistance in the zone between the contacting metal surfaces during the passage of heat flux depending on the time of application of mechanical loads is considered. The model is based on the transfer of heat through the contact zone in the presence of a heat-conducting gaseous medium. It is believed that the total thermal conductivity through the zone of contact of metal surfaces consists of conductivity through the contact pads of direct contact and intercontact cavities filled with gas, in this case air. Taking into account the provisions from the theory of contacting the surfaces of solids under long loads, the calculated dependences were obtained, allowing to determine contact thermistors for joints operating in the regime of long-term thermal mechanical loads without setting up time-consuming experiments. The given comparisons of the obtained experimental data and the calculated data give good convergence. The proposed technique allows specialists, when designing heat-stressed technical systems with components, to take into account the peculiarities of the formation of contact thermal resistances, taking into account the time of exposure to thermal and mechanical loads.