A comparative investigation of long-term oxidation behavior of selective laser melting–fabricated Inconel 718 at 650 °C. Issue 15 (14th August 2020)

• Record Type: Journal Article
• Authors: Luo, Yan-Wen; Zhang, Bin; Song, Zhu-Man; Li, Chang-Peng; Chen, Guo-Feng; Zhang, Guang-Ping
• Is Part Of: Journal of materials research. Volume 35:Issue 15(2020)
• Page Start: 2036
• Page End: 2045
• Publication Date: 2020-08-14
• Subjects: oxidation, -- alloy, -- microstructure; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1557/jmr.2020.98
• Languages: English
• ISSNs: 0884-2914

Abstract

Abstract: Abstract : The oxidation behavior of the selective laser melting (SLM)–fabricated Inconel 718 was investigated through isothermal oxidation testing at 650 °C for 500 h and compared with that of the as-cast and as-forged specimens at the same testing conditions. The effect of microstructure and surface roughness on the oxidation behavior of the SLM-fabricated, as-cast, and as-forged Inconel 718 specimens was examined. The result shows that Inconel 718 fabricated by SLM with the unique layer structure exhibited a better resistance to the 500 h oxidation at 650 °C compared with as-cast and as-forged 718 with coarse dendritic structure and uniform equiaxed grain microstructure, respectively. The influence of the surface roughness on the long-time oxidation resistance of SLM specimens is not pronounced compared with that of as-cast and as-forged specimens. The tiny dendrites instead of grain boundaries are a major influencing factor for the oxidation process of SLM specimens. The surface roughness has more evident influence on the oxidation resistance of as-forged specimens than that of the as-cast ones subjected to the 500 h oxidation at 650 °C.