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  • Effect of Two Different Point-Based Melt Scanning Strategies on the Microstructure of As-Built IN718 Parts Fabricated via EB-PBF System
Title: Effect of Two Different Point-Based Melt Scanning Strategies on the Microstructure of As-Built IN718 Parts Fabricated via EB-PBF System
Metal additive manufacturing has become integral to the modern aerospace and defense industry. Technologies such as powder bed fusion and direct energy deposition have reshaped these sectors. However, challenges like anisotropy and process-related defects still prevent the direct use of printed parts without post-processing. Electron beam powder bed fusion (EB-PBF) is well known for allowing builds at elevated temperatures and eliminating the need for stress relief. However, EB-PBF parts also experience epitaxial growth in the build direction, which causes anisotropy. This research explores two scanning strategies with spot melting techniques— stochastic and single directional—to fabricate IN718 parts using EB-PBF. After fabrication, the samples were analyzed using EBSD to evaluate grain formation in all directions. The findings suggest that point-based melting, guided by these strategies, can affect the microstructure in the build direction. This advancement offers the potential for tailoring controlled parts in future applications.  more » « less
Award ID(s):
2117801
PAR ID:
10635050
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
University of Texas at Austin
Date Published:
Subject(s) / Keyword(s):
Microstructure Control Electron Beam Melting Scanning Strategy Inconel 718 Spot Melting
Format(s):
Medium: X
Right(s):
open
Institution:
Austin, The University Of Texas At
Sponsoring Org:
National Science Foundation
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