Numerical estimation of the influence of pre-induced micro-cracks in the stress concentration zone on the SIFs of a lower suspension arm

Abstract

Structural steel is ductile in nature, this is the reason it is used in most of the Sectors in the manufacturing industry. Despite its structural strength, it faces compelling and challenging failures due to unstable, fatigue, dynamic and shock loads. 
 This research study evaluates the structural response on one of these loading conditions using the finite element method. The design of a lower suspension arm of an automobile is modelled in Solidworks 2020 and is solved for static elastic conditions in Ansys 2021 R1. A set of pre-induced fractures are then integrated into the computational model in the Stress concentration zones in different parts of the body and solved independently. A total of five micro-cracks are induced with each crack consisting of six contours. For the numerical simulation of lower suspension arm, real-time loading conditions must be attained to resemble real-world loading scenario. Hence, 4 modes of solving were chosen which would depict the real-world failure scenario where the suspension lower arm can attain maximum loads. The maximum load values are estimated in each mode and is integrated into the model with predefined boundary conditions for the computational approach. 
 A detailed numerical comparative conclusion is drawn regarding the SIFs of every mode and the crack that pertains maximum crack propagation rate.