Analysis and Evaluation of Fatigue Strength for Engine Bracket Considering Load Characteristics

Background: To obtain the load characteristics and fatigue characteristics of the engine bracket during the working process, the automobile engine bracket is taken as the research object, and the force characteristics are analyzed. Objective: This paper provides a theoretical basis for engine bracket design that improves the reliability and durability of the engine bracket. Methods: Under cyclic loading, the fatigue characteristics are analyzed through the bench test. According to the experimental results, the critical points of the engine bracket are examined. Results: According to the S-N curve, the estimated range of fatigue life of the engine bracket is from 34236 times to 127219 times. When the load level is low, the life span changes significantly with the stress. As the load increases, the fatigue life is less affected and shows a slight decrease. When the stress level is lower than the equivalent stress threshold value, the stress will not cause fatigue failure, and the specimen has an infinite life. Conclusion: This paper lays a foundation for the prediction of fatigue life and the bench test of fatigue durability of the engine bracket subjected to complex and variable random loads. The research method can also be used to estimate the fatigue life of other bearing parts.