About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
|
Symposium
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Advanced Materials for Harsh Environments
|
Presentation Title |
Microstructural Stability at Elevated Temperature of the Ni-based Electron Beam Welded Superalloys Dissimilar Joint |
Author(s) |
Oskar Dziuba, Grzegorz Cempura, Agnieszka Wusatowska-Sarnek, Adam Kruk |
On-Site Speaker (Planned) |
Agnieszka Wusatowska-Sarnek |
Abstract Scope |
ATI 718Plus® and Inconel 718 are precipitation-strengthened Ni-based superalloys exhibiting high strength and great corrosion resistance. Electron beam welding is the optimal joining process for Ni-based superalloys because of the narrow heat-affected zone and low level of introduced strains. The effect of annealing at 649 °C for up to 500 h on the microstructure of the dissimilar ATI 718Plus®/Inconel 718 fusion zone is not well known. Here we used various electron microscopy techniques to identify and characterize phases formed by the Laves phase transformation. Moreover, microhardness measurements were performed to assess the effect of microstructure evolution on mechanical properties. We found that Laves phase partially transformed into a complex cluster of precipitates contained δ/η and α-Cr phases. Moreover, main strengthening phases precipitated within the γ-matrix of the fusion zone. Our results show the instability of the Laves phase at elevated temperature and the effect of microstructural changes on mechanical properties. |