Microstructure and Mechanical Properties of Inconel 718 Produced by SLM and Subsequent Heat Treatment

Abstract:

The article presents results of selective laser melting of Inconel 718 superalloy. It was studied phase microstructure of the material obtained by selective laser melting and also the material after heat treatment. The phase composition of the initial powder material, the specimens after selective laser melting before and after heat treatment was studied. The effect of heat treatment on microstructure and mechanical properties of the specimens was shown. It was studied the mechanical behavior of the manufactured specimens before and after heat treatment at room and elevated temperatures as well. The results of impact tests and fractography of the specimens are presented. Mechanical tests showed that the specimens after heat treatment have decent mechanical properties comparable to hot-rolled material. Fractography showed that the obtained material is characterized by ductile failure mode with local elements of brittle fracture.

• Periodical: Key Engineering Materials (Volumes 651-653)
• Pages: 665-670
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.651-653.665
• Online since: July 2015
• Authors: Anatoly A. Popovich, Vadim Sh. Sufiiarov, Igor A. Polozov*, Evgenii V. Borisov
• Keywords: Additive Manufacturing, Inconel 718, Mechanical Property, Nickel Superalloy, Powder metallurgy, Selective Laser Melting, Superalloy

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