Microstructural evolution of laser solid forming Inconel 718 superalloy under different laser power

摘要

The present work studies the influence of laser power on the microstructure of as-deposited and solution treated Inconel 718 (IN718) superalloy by laser solid forming (LSF) method. The morphologies of Laves phase are discrepant under different laser power. The formation of Nb and Mo rich Laves phase is found in the as-deposited IN718 superalloy. The grains vary with increasing laser power from 850 W to 1100 W. Fine and relative uniform grains of IN718 superalloy are obtained under laser power 1000 W after solution treated at 1100 degrees C for 1 h. When the laser power is 1000 W, the obtained IN718 superalloy has the highest residual stress in the overlap area. (C) 2018 Elsevier B.V. All rights reserved.