Bending Fatigue Behavior Analysis and Fatigue Life Prediction of Spot-Welded Steel T-Profiles: An XFEM Analysis

Steel T-profiles are extensively used across various sectors due to their versatility and reliability. Spot welding plays a crucial role in their production. These profiles are subjected to cyclic bending loads in numerous engineering applications. Understanding the failure mechanisms is essential for enhancing fatigue resistance and extending the operational lifespan of spot-welded assemblies. Key aspects include accurately predicting where damage initiates, how it propagates under increasing cyclic loads, and the failure point. For this purpose, XFEM analysis was conducted and validated with experimental results from the literature. The study emphasizes the significant impact of bending moment magnitude, load ratio, the diameter of spot welds, and component thickness on the fatigue performance of spot-welded assemblies under bending loads. All these parameters significantly affected the fatigue response. Notably, thinner components showed 8.55 times faster crack propagation, accompanied by more localized and severe cracking.