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  • The Difficulty of Measuring Surface Topography in Additive Manufacturing: A Comparison Between Measured and True Surface Features of Binder-Jet Printed Samples

This content will become publicly available on April 29, 2026

Title: The Difficulty of Measuring Surface Topography in Additive Manufacturing: A Comparison Between Measured and True Surface Features of Binder-Jet Printed Samples
Surface topography represents a critical barrier to the advancement of additive manufacturing (AM). Because some internal features cannot be polished and because of the growing trend of in situ process monitoring, it is important to understand the as-built surface topography of AM components. Here we highlight the challenges of using industry-standard surface-measurement techniques on binder-jet-printed parts. We measured the topography of binder-jet-printed Inconel alloy 625 samples in their green state and over the course of sintering; this system allowed the investigation of identical starting materials undergoing systematic changes in topography. Specifically, we compared the results from industry-standard surface-measurement techniques—optical interferometry, 3D microscopy (by fringe projection), and stylus profilometry—against the “true topography,” as revealed by cross-sectional scanning electron microscopy. While the true topography changed significantly with sintering, the industry-standard techniques detected no change in the root-mean-square height because of complex surface features, including multi-scale topography, overhangs, and steep surface slopes. While these findings do not invalidate the use of industry-standard techniques for binder-jet-printed samples, they demonstrate a challenge in their application, and they motivate the development of new metrics and new techniques to more accurately describe surface topography in AM.  more » « less
Award ID(s):
2400999
PAR ID:
10598371
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Journal of Tribology
Date Published:
Journal Name:
Journal of Tribology
Volume:
147
Issue:
9
ISSN:
0742-4787
Subject(s) / Keyword(s):
Keywords- Scanning electron microscopy Inconel alloy 625 binder jetting 3D printing
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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