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Title: The performance of Cu-based friction material in dry clutch engagement
An enhanced Cu-based friction material was prepared by the powder metallurgy techniques and proposed for use in the dry clutch system. The friction characteristics and wear rate of this friction material sliding against 65Mn steel are obtained using Universal Material Tester-5. The friction pairs were subjected to two operating variables, which are sliding speed and temperature. The effect of these variables during the engagement process of the friction pairs is investigated. Knowing the normal applied force and dimension of the clutch disc, the dynamic friction coefficient was translated to friction torque capacity with time. It was found that instability can be excited at low operational conditions when the resulting friction coefficient is high. At 25 ℃, the dynamic friction torque oscillates with time likewise at 400 ℃. Generally, a more stable friction torque is obtained when the sliding speed is varied compared to varying the temperatures. Moreover, the influence of the operating temperatures and sliding speeds on thermal buckling and thermoelastic instability of the friction disc is the second consideration in this work. The onset of thermoelastic instability occurs when the sliding speed exceeded 200 r/min and the results for the growth rate of hot spots were found to agree well with the critical speed of the system. Also, thermal buckling was highly dependent on the temperature difference between the inner and outer radius of the friction disc.  more » « less
Award ID(s):
1928876
NSF-PAR ID:
10465169
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology
Volume:
235
Issue:
6
ISSN:
1350-6501
Page Range / eLocation ID:
1114 to 1123
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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