Abstract
In this study, the fatigue characteristics of additively-formed multi-principal element alloy (MPEA) of Co1.5CrFeNi1.5Ti0.5Mo0.1 (CoCrFeNiTiMo alloy) were systematically compared with conventional hot-rolled and additively-formed Alloy 718 nickel-based super alloy, which have comparable mechanical properties. Evaluated fatigue properties were the low-to high-cycle fatigue strengths of plane and notched specimens, and long/short fatigue crack growth (FCG) resistance. The results showed the fatigue strength of CoCrFeNiTiMo alloy to be comparable to that of Alloy 718 for smooth specimens, while the fatigue strength of notched specimens was 50% higher. Superior notch fatigue strength can be quantitatively explained in terms of outstanding long fatigue crack growth resistance. Regardless of load ratio, CoCrFeNiTiMo exhibits superior FCG resistance that greatly surpasses that of conventional Fe and Ni alloys. In contrast, the short FCG resistance of CoCrFeNiTiMo was comparable to that of Alloy 718, which corresponds to the fatigue strength level of a smooth specimen. Investigation of fatigue fracture surface and microscopic slip deformation morphology around the fatigue crack indicates that CoCrFeNiTiMo alloy exhibits more planar slip deformation than Alloy 718. Slip constraint stimulated by slip planarity appears to have an important role in short and long FCG resistance when cracks cross grain boundaries.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
