MICROSTRUCTURE EVOLUTION OF INCONEL 625 IN 3D LASER-BASED DIRECTED ENERGY DEPOSITION

Abstract

In recent years, there has been a notable increase in the utilization of Inconel 625 material in
metal 3D printing, which employs laser beam technology, particularly in industrial applications.
This trend is especially evident in situations where intricate components with exceptional strength,
corrosion resistance, and thermal stability are required at elevated operational temperatures. The
microstructures of Inconel 625-printed components significantly influence their mechanical
properties, corrosion resistance, and overall performance. This study unveils the initial findings
regarding microstructure transformations during the 3D printing process of Inconel 625 material,
commencing from the initial powder particles to the formation of a single printed layer on the
substrate. The research reveals that Inconel 625 powder particles, initially featuring an equiaxed
grain structure, undergo rapid melting when combined with the substrate material, subsequently
solidifying and resulting in the formation of needle-like and dendritic microstructures. These
microstructural changes are attributed to the distinct heating regimes experienced during the
powder particle formation and printing process. This research provides fundamental and practical
insights into the microstructure evolution of Inconel 625 in laser-based directed energy deposition,
serving as a crucial reference for future studies in this field.