In situ interlayer hot forging arc plasma directed energy deposition of Inconel® 625: microstructure evolution during heat treatments

The study reports that the combined use of in situ interlayer hot forging and post-deposition heat treatment (PDHT) could alter typical coarse oriented microstructure Ni-based superalloy 625 obtained by arc plasma directed energy deposition (DED) to a fine non-oriented condition. In synchrotron X-ray diffraction electron backscatter showed high-temperature (1100 °C/ 1 h) PDHT induced significant recrystallization, leading grain refinement low texture index, while partially dissolving deleterious Laves δ phases. Low-temperature (980 had limited effect on size formation secondary It is shown conventional treatments applied DED are not conducive optimized features. enough crystal defects promote static recrystallization during PDHT. Besides, met AMS 5662 requirements.