Challenging these notions, Dr. Ankur Chauhan and his team from the Department of Materials Engineering, Indian Institute of Science (IISc) Bangalore, systematically explored the role of two critical microstructural features in enhancing the low-cycle fatigue (LCF) performance of alloys in the Cr-Mn-Fe-Co-Ni system.
By adjusting the Cr/Ni ratio, they synthesized two single-phase face-centered cubic (FCC) MPEAs with distinct SFEs. The low-SFE alloy exhibited 10–20% higher cyclic strength than the high-SFE alloy while maintaining a comparable fatigue life. This improvement is attributed to the delayed evolution of dislocation substructures and a lower crack propagation rate in the low-SFE alloy compared to the high-SFE alloy.
Additionally, the team developed a dual-phase alloy that demonstrated a 50–65% increase in cyclic strength over the single-phase low-SFE alloy while maintaining a similar fatigue life.
Advanced characterization techniques, including electron microscopy and in-situ X-ray diffraction, play a crucial role in elucidating the underlying mechanisms of fatigue damage. These insights, coupled with computational modeling, facilitate the design and optimization of fatigue-resistant alloys tailored to specific application requirements.
Ultimately, the relentless pursuit of better fatigue-resistant alloys is not merely an academic exercise. It is a vital endeavor that underpins the safety and reliability of infrastructure, transportation systems, and countless other technologies upon which modern society depends. Continued research and development in this area are paramount to advancing engineering capabilities and ensuring the long-term integrity of engineered structures.
