Thermo‐Mechanical Fatigue, Crack Evolution, and Fracture Reliability of Lightweight High‐Power‐Density Diesel Pistons: A Review

Abstract

The higher power density and lightweight design of diesel pistons impose severe thermo‐mechanical demands. This review summarizes research on thermo‐mechanical fatigue, crack evolution, and fracture reliability in lightweight, high‐power‐density pistons. The review examines service loading, critical failure‐prone regions, and coupled fatigue–creep–oxidation damage. It shows why single‐mechanism models are inadequate under realistic conditions. The review compares crack initiation and propagation in Al–Si alloy, steel, and steel crown‐aluminum skirt composite pistons. Life‐prediction methods ranging from empirical Coffin–Manson models to continuum damage mechanics and machine learning–assisted frameworks are critically assessed. The review also examines mitigation strategies involving materials, structural design, advanced manufacturing, and thermal barrier coatings. Key research needs include multiscale in situ characterization, physics‐informed data‐driven prediction, intelligent material design, and real‐time health monitoring to enable the reliability‐oriented design of next‐generation diesel pistons.