# Wear Characteristics of Different Groove-Shaped Friction Pairs of a Friction Clutch
###### Abstract  
To investigate the influence of the groove shape of friction disks on the wear of a friction clutch friction pair, a wear calculation model that considers the actual sliding distance between the friction clutch friction pair is presented based on the Archard adhesive wear model. The wear of three different groove-shaped friction pairs was calculated and analyzed. The wear test was carried out on the SAE#2 testing rig to obtain the actual wear amount and verify the accuracy and validity of the mathematical model. The results show that, among the three types of grooves, the friction disks with waffle grooves were the most prone to wear, followed by three-way parallel grooves. The wear performance of the two-way parallel grooves was the best, and the wear from one-time engagement can better reflect the change in the dynamic engagement of the friction pair. With the increase in the engagement time, the increase of the wear amount decreases.  
wet friction clutch; friction pair; groove shape; wear; SAE#2 testing rig +
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friction disk within a short interval, so as to prevent the function of the friction disks from decreasing due to the fact of wear and affecting the wear calculation. [PERSON] [5] analyzed the wear of the wet clutch during the engagement process based on the Reynolds equation and the rough surface contact model. The influence of the plastic wear coefficient and the elastic wear coefficient on the overall friction disk wear was considered, but the influence of the running-in number was not considered. Based on the total sliding distance of the friction pair and Archard wear theory, [PERSON] [6] simulates the specific engagement time during the engagement process of the friction pair. [PERSON] [7] calculated the friction disk wear by regarding the sliding distance as the product of speed and time directly and carried out the test on the clutch bench in accordance with the wet clutch friction element test method. [PERSON] [8] studied the influence of the friction disk contact ratio on the wear by regarding the sliding distance and time as a proportional relationship and analyzed the quantitative relationship between the friction disk and wear with different contact ratios.  
In conclusion, most of the calculations of the surface wear of friction disks were measured by theoretical calculations or directly through experiments, especially the pin experiment, that is, the fixed pin cannot move, and the friction disk rotates. As for the Archard model, the sliding distance is regarded as the product of rotational speed and time. In the actual work of the friction clutch, the active disk engages with the driven piece with the initial speed difference. The speed of the active disk is reduced, and the speed of the driven disk is increased; then, the speed is completely consistent and the engagement process is completed. The sliding distance in the engagement process is nonlinear and time-varying, and the linearly changing sliding distance in the pin-disk experiment cannot accurately reflect the actual situation. Therefore, this paper proposes a method to calculate the actual sliding distance of friction pairs and which can calculate the nonlinear time-varying sliding distance in the process of friction pair jointing, solving the actual wear of friction pairs. For different groove-shaped friction disks, this paper calculates the amount of wear on friction disks during a single engagement, determines which groove shapes produce less wear during actual working conditions, and uses friction disks with different groove shapes to carry out wear tests on the test machine, demonstrating the accuracy of the theoretical calculations and providing references for the design and analysis of friction clutches.