Simulation And Verification Of Friction Temperature Fields Of Copper-Based Friction Materials And C/C-SiC Composites

Powder metallurgy copper-based friction materials excel in friction and wear properties,which are widely used in various high-energy braking condition.Paired with the new brake materials C/C-SiC composites,it is expected to meet the evergrowing demanding service conditions arising from the increase in operating speed and bearing capacity of vehicles.Based on finite element simulation calculations,the research on the pairing of copper-based friction materials with C/C-SiC composites is implemented through a combination of theoretical analysis and experimental research.The characteristics of the friction temperature field are explored,based on which the influence of copper-based friction material composition and parameter influences on the temperature field is deeply explored.The relations of the formation of the friction layer and the influence of the friction layer on the temperature field are analyzed.The main conclusions are as follows:（1）This work studys the similarities and differences among temperature fields of various brake ring pairings,which are ring pairing of PM-Cu-A with C/C-SiC,ring pairing of PM-Cu-A with alloy steel and ring pairing of PM-Cu-A with cast steel.PM-Cu-A has the highest temperature rise with C/C-SiC ring braking,and under 6667 r/min braking conditions,the maximum temperature rise is about 180°C higher than the friction pair where the alloy steel ring and the cast steel ring are located.This requires copper-based friction materials paired with C/C-SiC composites to have higher high temperature friction and wear properties.（2）The differences between the friction temperature field of different components of copper-based friction materials paired with C/C-SiC rings are studied.The thermal conductivity of PM-Cu-B and PM-Cu-C with ceramic components Si O₂ and Zr O₂ added has been reduced,but the coefficient of friction is effectively increased when braking with C/C-SiC rings.Especially under the high-energy braking conditions of 6667 r/min,the PM-Cu-B paired with C/C-SiC ring has the maximum friction coefficient and the shortest braking time.The maximum temperature rise is 110°C higher than that of PM-Cu-C and carbon ceramic rings.（3）Friction layer formation and its effect on frictional wear properties and temperature fields are studied.The addition of ceramic components improves the high-temperature friction and wear performance of copper-based friction materials,and its friction layer shows good continuity and denstrictivity under high temperature and pressure,which is conducive to improving the stability of high-speed braking and reducing the wear rate of friction materials.High thermal conductivity or low thickness of the friction layer implies smaller on the temperature field.Conversely,more significance of the thermal barrier effect of the friction layer,which affects the heat flow distribution,results to greater impact on the temperature field.