Influence of the microstructural homogeneity on the high-temperature oxidation behavior of a single crystalline Ni-base superalloy
Year: 2021
Type: article
Abstract: Additive manufacturing by means of selective electron beam melting (SEBM) was recently demonstrated as an intriguing technique for the generation of single crystalline (SX) CMSX-4, a commercial Ni-base superalloy. The objective of this study is to compare the high-temperature oxidation resistance of SX SEBM-samples to their conventional counterparts which are derived by Bridgman investment casting. Therefore, time-resolved isothermal gravimetric analysis (TGA) was conducted at 850 and 1050 °C in synthetic air for 100 h. Due to solution annealing prior to oxidation, solidification induced elemental segregations could be homogenized completely in case of the SEBM-material, whereas they remained apparent for the conventional Bridgman samples. With residual elemental segregations inhomogeneous oxide scales emerged during exposure, exhibiting above-average scale thicknesses upon dendritic regions. Consequently, TGA revealed a higher mass gain in case of present segregations. In conclusion, a better high temperature oxidation resistance is observed for the homogeneous SEBM material.
Source: Scripta Materialia
Authors: J. Pistor, S.P. Hagen, S. Virtanen, C. Körner
Institution: Friedrich-Alexander-Universität Erlangen-Nürnberg
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,000
Funder: Deutsche Forschungsgemeinschaft
Award: G125635838
OpenAlex ID: W3202451353