Fatigue and Durability Based Analysis and Design of Lower Control Arm with Composite Materials

Abstract

In order to satisfy the fuel efficiency regulation and CO2 emissions regulation, researches to reduce the weight of automobile body as well as its components have been actively carried out recently. Fatigue analysis is also becoming more important in terms of securing safety as fracture occurs even under lower than the yield stress, even if there is sufficient margin in the strength. In particular, lower control arm is a component that affects the steering safety and ride comfort in suspension system, it is essential to examine whether it satisfies the safety depending on durability. In this paper, we conducted the fatigue and durability based analysis of lower control arm with carbon fiber reinforced plastics, which is a representative composite material. For this, stress and stiffness analysis under given load conditions are performed through finite element analysis, and we verify whether it satisfies the load and stiffness conditions or not. And also, the inertia relief method for finite element analysis is utilized to simulate the
static load conditions. Based on these results, the fatigue life was predicted by the stress-life method. We also applied the Smith-Watson-Topper index to account for the average stress effect.