Fatigue life assessment of vehicle coil spring using finite element analysis under random strain loads in time domain

Purpose This paper aims to assess the fatigue life characteristics of vehicle coil spring under random strain load in the time domain. Cyclic random road loads caused fatigue failure for automotive components during their operating condition. . Design/methodology/approach The coil spring model is developed through finite element analysis software. The critical region and fatigue life cycle of coil spring is evaluated through finite element analysis. The experimental is set up to capture the random strain signal of the rural, highway and campus road. The sampling rate of the random strain signals data captured were 500 Hz in 150 s. Then, fatigue life is assessed through Goodman, Brown-Miller, Fatemi-Socie, Wang-Brown fatigue life models. Goodman model is evaluated through finite element analysis in order to compare with fatigue experimental results. Findings The fatigue life was estimated for Brown-Miller model is the highest (4.32E4, 4.10E4, and 3.73E4 cycles/block for rural, highway and campus respectively) followed by Goodman model, Brown-Miller, Fatemi-Socie and Wang-Brown models respectively. The conservative fatigue life 1:2 and 2:1 data scattering approach is proposed in order to determine the acceptability of the data. Originality/value Hence, the proposed fatigue life models can be used to assess multiaxial fatigue under random strain signals for the automobile coil spring.