Effect of porosity and eutectics on the high-temperature low-cycle fatigue performance of a nickel-base single-crystal superalloy. (October 2018)

• Record Type: Journal Article
• Authors: Ruttert, Benjamin; Meid, Carla; Mujica Roncery, Lais; Lopez-Galilea, Inmaculada; Bartsch, Marion; Theisen, Werner
• Is Part Of: Scripta materialia. Number 155(2018)
• Page Start: 139
• Page End: 143
• Publication Date: 2018-10
• Subjects: Electron backscatter diffraction (EBSD) -- Hot isostatic pressing (HIP) -- Low-cycle fatigue -- Microstructure -- Single-crystal superalloy; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2018.06.036
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: This work investigates the separate influence of porosity and γ/γ′-eutectics on the low-cycle fatigue life of a single-crystal Ni-base superalloy at high temperatures. A conventional vacuum furnace heat-treatment but also integrated heat-treatments in a hot isostatic press are applied to produce different material variants of the same alloy. High-resolution electron microscopy revealed that both pores and γ/γ′-eutectics act as crack starters, thus initiating early failure. Moreover, the results indicate that remaining γ/γ′-eutectics can weaken the fatigue resistance even more than pores. Furthermore, the results confirm the beneficial effect of proper integrated hot isostatic pressing heat-treatments on the fatigue performance. Graphical abstract: Unlabelled Image