Research On The Tribology Performance And Application Of Micro-automobile Clutch

Clutch is a key component in an automotive section, which ensures a smooth start and shift as well as a portable control of automobiles. As to a micro-automotive clutch, performance of friction plate directly affects its useful-time and driveline stability. Presently intensive studies are taken on wear and friction performance of friction plate and brake pads for clutches in special vehicles both at home and abroad, while less researches are carried out on wear and friction performance, heat-load performance and life estimation for those in micro-automobiles, resulting in a gap with the prosperous development of micro-automobile industry. Hence a research on the performance of clutch's friction plate in micro-automobiles is imperative.The purpose of this paper is to provide a theoretical basis and data support for optimization of clutch structures in micro-automobiles, analysis of existing faults such as early abnormal wear of the clutch's friction plate, design of clutch systems, and selection of clutch friction materials.This paper mainly focuses on five important aspects as follows:1) Design a material with a composition and proportion appropriate to micro-automotive clutches and prepare a test sample based on production process of clutch friction material.2) The factors that affect the friction and wear performances of the clutch friction plate are proposed by orthogonal test, whose primary and secondary order is:load P, speed V, the interaction of load and speed Px V, the interaction of ambient temperature and speed T x V, ambient temperature and load T X P, the ambient temperature T; the best test conditions of friction and wear properties are proposed as follows:a ambient temperature of 100℃, a load of 150N, and with the relative speed of 430r/min, and the friction performance test is designed extensively.3) Provide the general law that load, speed and PV value effect on the friction and wear properties of clutch friction plate in micro-vehicle.Establish the friction coefficient and wear mathematical model with load and speed.4) According to the principles that the heat of friction generate and transmit, the temperature distribution law of the friction plate surface was obtained, which was the highest temperature lies in the edge of the friction plate and the temperature was gradually decreased in a step way along the direction of diameter; and a formula for calculating the average temperature of friction surface in the condition of once connection was deduced; and the heat fading phenomenon of friction plate was explained based on tribology theory, whose essence was the sharp decrease of friction coefficient due to the lubricating layer generated by the thermal decomposition of resin.5) Five friction models for friction process was proposed through concluding the friction and wear mechanism of friction plates in micro-automobiles, and the wear mechanism combined with the surface morphology of friction plate was analyzed. The friction material wear rate Iw was calculated, according to the statistical methods of test data, so actual life mileage can be estimated exactly.