Optimization and Fatigue Life Enhancement of Crankshafts in Internal Combustion Engines: A Comprehensive Review of Material, Geometry, and Finite Element Analysis

A crucial part of internal combustion engines, the crankshaft transforms the linear action of pistons into rotating motion. Due to its complex geometry and exposure to high cyclic loads, the crankshaft is prone to fatigue failure, particularly in fillet regions. This study provides a comprehensive review of existing research on crankshaft optimization, focusing on material selection, geometric modifications, and fatigue life enhancement techniques. The review highlights the importance of finite element analysis (FEA) in predicting stress distribution, fatigue life, and failure mechanisms. Various optimization strategies, such as fillet rolling, surface treatments, and material substitution, are discussed to improve crankshaft durability and performance. The study also explores th]e role of advanced manufacturing techniques, including shot peening and induction hardening, in enhancing fatigue resistance. By synthesizing findings from numerous studies, this research identifies key factors influencing crankshaft performance, such as residual stresses, fillet radius optimization, and dynamic loading conditions. The conclusions emphasize the need for a multidisciplinary approach combining material science, mechanical design, and computational modeling to achieve cost-effective and reliable crankshaft designs for modern automotive applications.