Novel material architecture for enhanced high cycle fatigue life in turbofan engine fan blades

High Cycle Fatigue (HCF) is a critical failure mode in turbofan blades, primarily driven by resonance phenomena when the blade’s natural frequency aligns with engine-induced excitations. Traditional approaches to mitigate HCF often involve geometric modifications or damping treatments, which can adversely affect aerodynamic performance or increase component weight. This study explores alternative methodologies to strategically alter the natural frequency of turbofan blades while maintaining aerodynamic efficiency and structural integrity. A novel material architecture is proposed, consisting of a dual-metallic configuration with a high-stiffness core and a lightweight, fatigue-resistant outer shell. This design enables precise tuning of the blade’s dynamic response by leveraging the contrasting mechanical properties of the core and outer materials. The dual-metallic structure shifts the natural frequency away from critical excitation zones, thereby reducing the risk of resonance-induced fatigue failure. Additionally, the hybrid configuration contributes to weight reduction compared to conventional monolithic blade designs, offering further performance benefits. Comprehensive Finite Element Analysis (FEA) is employed to evaluate modal characteristics and stress distribution of turbofan blades. Results indicate that the proposed architecture achieves a favorable balance between dynamic stability, structural robustness, and aerodynamic performance. The dual-metallic blade design not only improves HCF life but also provides a scalable framework for future turbofan blade optimization. This study demonstrates that material architecture innovation offers a promising pathway for enhancing blade durability and performance in modern aero-engine applications, without compromising critical design constraints.