High temperature oxidation of inconel 939 produced by additive manufacturing
Alberto Visibile, K.O. Gunduz, Mohammad Sattari, Irina Fedorova, M. Halvarsson, Jan Froitzheim
Abstract
High temperature oxidation of additively manufactured (Laser-powder bed fusion) IN939 (AM IN939) was studied at 900°C in dry air for 168 hours. AM IN939 cut parallel/perpendicular to the building direction, including conventionally manufactured (CM) IN939, were exposed to assess the influence of AM microstructure and its inherent anisotropy on oxidation properties. Microstructural anisotropy had no significant impact on oxidation properties. AM and CM IN939 exhibited nearly identical mass gains, yet local spallation was observed in the former. Further investigation involved oxidation of heat-treated AM IN939, revealing improved adhesion, possibly due to transformation of fine dendritic/cellular structure into coarse equiaxed grains.