Fretting Fatigue Of Automotive Leaf Spring

Author:  Mutoh, Tanaka, Takeda
Source:  Fat.of Engrg.Mater.and Struc.Vol.I,15-16 Sept.
Doc ID:  1986052
Year of Publication:  1986
Abstract:  
fretting fatigue tests on leaf springs and small axial-loading specimens were carried out under constant loading and random loading simulating field load spectra. The results for leaf springs were compared with literature data on similar springs. The behavior of fretting fatigue crack initiation and propagation in the leaf springs was found to be almost the same as in the small laboratory specimen. No significant differences between their fretted surfaces and also between their fatigue fracture surfaces were observed. Random loading reduced the fretting fatigue lives by a factor of 1.5. The effect of shot peening on fretting fatigue was also investigated. Shot peening improved the fretting fatigue strengths in both specimens by a factor of two. The residual compressive stresses induced by the shot peening process were responsible for the improvement. It is suggested that the fretting fatigue life of leaf springs can be estimated from that of laboratory specimens, provided the clamping pressures and the relative slip amplitudes of both are of the same magnitude. Descriptors: Automotive components-- Mechanical properties; Leaf springs-- Mechanical properties; Spring steels-- Mechanical properties; Fatigue life-- Deformation effects; Fretting; Shot peening