Fatigue damage occurs when a component or assembly is subjected to a varying load sequence, leading to microscopic plasticity in notches, rough surfaces, voids, or welds that can form and grow fatigue cracks. These cracks continue to grow until the structure can no longer support the load, resulting in catastrophic failure. Predicting fatigue life or critical failure locations is impossible using a simple static Finite Element analysis, as areas of high Von-Mises stress are not necessarily where fatigue failure will occur. Fatigue is categorized into Low Cycle Fatigue (LCF) for shorter lives and High Cycle Fatigue (HCF) for longer-lasting structures. The most basic method for fatigue analysis is stress-based, using Rainflow Cycle Counting and Stress-Life (SN) data to calculate and accumulate fatigue damage, suitable for HCF applications. 

For LCF applications, strain-based fatigue analysis is necessary to account for both linear elastic and non-linear plastic strain, predicting life to crack initiation. In 2D models, Neuber Analysis is used to calculate the elastic and plastic strain at failure locations. In cases such as automotive parts, failure occurs rapidly after crack initiation, whereas in more ductile materials like those used in aerospace, catastrophic failure occurs after significant crack growth. Fracture mechanics are used to predict crack growth rates in these cases. Through our CAE fatigue analysis services, we utilize stress, strain methods directly from 3D CAD models, combined with advanced signal processing software to accurately estimate input load sequences. Our approach, supported by an extensive material database and advanced algorithms, allows us to identify critical planes and optimize designs, validated through cost-effective lab testing to ensure accurate reproduction of usage conditions.