针对离合器滑摩过程中摩擦副元件温度场和应力场分布，建立摩擦热流密度与真实接触面积的动态滑摩过程分析模型，通过动态测温和静态比压试验验证了理论模型对接触比压分布研究的适用性。引入了摩擦副元件动态滑摩热弹形变系数Kα、静态不均匀接触系数Kδ和离合器接触比压扰动系数K。K值为接触比压最大值与名义平均接触比压之比，K值越大，配对摩擦副接触界面比压扰动越大，表明配对摩擦副接触特性越差，真实接触面积越小，离合器越可能出现局部高压与高温区。理论分析与试验结果表明：所研究的铜基粉末冶金摩擦材料与65Mn对偶钢片组成的配对摩擦副：在低、中摩擦热流密度时，真实接触面积为名义接触面积的40%～60%；高摩擦热流密度时，真实接触面积约为名义接触面积20%～40%；当达到或超过临界摩擦热流密度时，配对摩擦副真实接触面积仅为名义接触面积的10%～15%。
李和言
,
王宇森
,
熊涔博
,
陈飞
,
李明阳
,
杨硕
. 离合器配对摩擦副径向温度梯度对接触比压的影响[J]. 机械工程学报, 2018
, 54(1)
: 136
-143
.
DOI: 10.3901/JME.2018.01.136
Based on numerical results of temperature field and stress field, a theoretical model is built to investigate thermal flux and actual contact area of the clutch friction pair during slipping process, which is validated by continuous temperature measurements and static pressure tests. Several coefficients are introduced to express slipping process of clutch friction pair:dynamic slipping thermal deformation coefficient Kα, static uneven contact coefficient Kδ, and interface pressure perturbation coefficient K. Occurrence probability of high-pressure and high-temperature areas is greater by the smaller actual contact area which leads to a larger value of interface pressure coefficient K as well. Calculation and experiment results indicate that the actual contact area ratio ranges from 40% to 60% for copper-base friction pair with low and middle friction thermal flux, and 20% to 40% with high friction thermal flux. While the friction thermal flux reaches at or above the limit, the ratio of the actual contact area to the nominal contact area is only 10%-15%.
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