Mathematical modelling for fatigue life prediction of a symmetrical 65Si7 leaf spring

摘要

Leaf spring is a suspension component which is designed to sustain a required fatigue life before its failure or permanent set. The fatigue life of a leaf spring depends upon the various factors like geometry, design, material, processing, fatigue strength reduction and some uncontrollable factors. To determine the effect of variation of individual factor on the fatigue life is always a challenging task as the experimental procedure is time consuming and costly. Also no such attempt has been made to predict this effect. The work presented in this paper depicts the effect of variation of an individual factor on the fatigue life of a leaf spring. A computer program has been written in FORTRAN, for determination of the fatigue life of a light commercial vehicle, has been validated experimentally. Two processing factors, five strength reduction factors, one design factor, one material factor and two geometry factors have been considered for investigation in this work. The effect of variation of one factor at time on the fatigue life of the leaf spring has been determined and modelled using statistical tool NCSS. The regression model has been depicted and validated analytically and experimentally.