Abstract: The model of buckling nodes for annular thin plate was developed to explain the deformation of separator discs in multi-disc clutches. The influence of the thickness and radial temperature difference on the buckling of separator discs was studied. Sliding experiments of multi-disc clutch were conducted. The analysis of buckling model and the results of the sliding experiments show that the radial stress caused by radial temperature gradient can lead to buckling deformation of the discs. Separator discs can be buckled while radial stress reaches to the preferred value. Radial thermal stresses caused by temperature gradient can not be ignored. The critical buckling stresses of the separator discs are different for different orders, and the critical buckling load of the lower buckling order is smaller. The buckling critical loads are different under different boundary conditions, and the critical buckling load under the condition simple support on the outside diameter is smaller. The critical radial buckling stress can be enhanced by increasing the disc thickness. The thickness of the separator discs under different boundary conditions are both increased by 1 mm, and the anti-buckling ability of the discs are increased by 125.4% and 125.9%, respectively.

Key words: vehicle engineering, multi-disc clutches, separator discs, radial thermal stress, buckling model, critical buckling stresses