Abstract
The strain-controlled low cycle fatigue behavior of two advanced nickel-base eutectics, AG-170 and Nitac 14B, was studied at 825 °C in argon. Heat treatment to alter the γ/γ′ distribution was the principal experimental variable. Testing consisted of continuous cycling (0.2 Hz) and cycling with the imposition of a 120 s hold at the maximum tensile strain. Both alloys obeyed the Coffin-Manson relation under all test conditions. Aging had no effect on fatigue life in continuous cycling. As-directionally solidified (as-DS) Nitac 14B displayed a reduction in fatigue resistance with hold time, whereas aged Nitac 14B and aged AG-170 fell in the same scatterband with a hold time as with continuous testing. The lack of a hold time effect on aged material is attributed to the development of a compressive mean stress and a decrease in fiber damage owing to the aging treatment. The low cycle fatigue resistances of AG-170 and Nitac 14B are compared with those of several current nickel-base superalloys.
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.
