Crack Growth Studies in a welded Ni-base superalloy

• It is well known that the introduction of sustained tensile loads during high-temperaturefatigue (dwell-fatigue) significantly increases the crack propagation rates in many superalloys. Onesuch superalloy is the Ni-Fe based Alloy 718, which is a high-strength corrosion resistant alloy usedin gas turbines and jet engines. As the problem is typically more pronounced in fine-grainedmaterials, the main body of existing literature is devoted to the characterization of sheets or forgingsof Alloy 718. However, as welded components are being used in increasingly demandingapplications, there is a need to understand the behavior. The present study is focused on theinteraction of the propagating crack with the complex microstructure in Alloy 718 weld metalduring cyclic and dwell-fatigue loading at 550 °C and 650 °C.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Annan teknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Other Engineering and Technologies (hsv//eng)

Nyckelord

laser weld

dwell fatigue

Alloy 718

electron microscopy

Superalloy

crack growth

Publikations- och innehållstyp

kon (ämneskategori)

ref (ämneskategori)