Evaluation of notch effects in low cycle fatigue of alloy 718 using critical distances

Eriksson, RobertLinköpings universitet,Mekanik och hållfasthetslära,Tekniska fakulteten (author)

Funding Agencies|European Union [653941]
Gas turbine disks contain many notch-like features acting as stress raisers. The fatigue life based on the notch root stress may be overly conservative as the steep stress gradient in front of the notch may give rise to so-called notch support. In the current work, the theory of critical distances was applied to the prediction of the total fatigue life of low cycle fatigued, notched specimens made from alloy 718. The fatigue tests were performed at 450 degrees C and 550 degrees C. It was found that, for lives shorter than 5000-10000 cycles, the notched specimens had longer lives than would have been expected based on the notch root strain. For lives longer than 5000-10000 cycles, there were no notch support. The life prediction for notched specimens could be significantly improved by basing the prediction on the strain chosen some distance from the notch (the critical distance). An expression for calculating the critical distance based on the notch root strain was suggested.

Simonsson, KjellLinköpings universitet,Mekanik och hållfasthetslära,Tekniska fakulteten(Swepub:liu)kjesi56 (author)
Leidermark, DanielLinköpings universitet,Mekanik och hållfasthetslära,Tekniska fakulteten(Swepub:liu)danle89 (author)
Moverare, JohanLinköpings universitet,Konstruktionsmaterial,Tekniska fakulteten(Swepub:liu)johmo31 (author)
Linköpings universitetMekanik och hållfasthetslära (creator_code:org_t)

By the author/editor: Eriksson, Robert; Simonsson, Kjell; Leidermark, Dani ...; Moverare, Johan

About the subject

ENGINEERING AND TECHNOLOGY: ENGINEERING AND ...; and Mechanical Engin ...; and Energy Engineeri ...

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.