Fatigue life prediction analysis of automobile suspension system bracket considering residual stress due to thermal stress.

Kim, Kee Joo; Lee, Jae-Woong; Park, Jun-Hyub

The stabilizer-bracket, one of the parts constituting the suspension, is mainly manufactured through welding due to its complicated shape. Shape fabrication through welding has residual stress due to mechanical defects or thermal stress, which are important factors in the design of automotive parts that prioritize safety in the early stages of manufacturing. As a result, it receives various types of repetitive loads. Since these factors are one of the factors that have a great influence on the fatigue life of parts, various life evaluation methods that take them into account have been proposed. Therefore, in this study, the reliability of parts was verified by predicting the fatigue life through fatigue test and CAE (computer aided engineering) analysis in consideration of the residual stress and various cyclic loads of the stabilizer-bracket using the finite element method. According to the results of fatigue life analysis, the value using S-W-T and Morrow's formula had a longer life than the result of the method without considering the average stress. From this, considering the design criteria to guarantee vehicle durability of 200000 km, it was calculated that the fatigue life was 11.4 times more than the design criteria, excluding the case in which the average stress was not considered.

FATIGUE life; AUTOMOBILE springs & suspension; RESIDUAL stresses; MOTOR vehicle springs & suspension; THERMAL stresses; STRAINS & stresses (Mechanics); CYCLIC loads

Journal of Mechanical Science & Technology, 2024, Vol 38, Issue 6, p3047

1738-494X

Academic Journal

10.1007/s12206-024-0524-z