Page 140 - MSAM-4-2

Materials Science in

Additive Manufacturing

ORIGINAL RESEARCH ARTICLE
Powder spreading behavior of bimodal ceramics

in the binder jetting process

Kazi Safowan Shahed 1 , Willem Groeneveld-Meijer , Matthew Lear ,
2
3
Jeremy Schreiber , and Guha Manogharan *
3
1,2
1 Department of Industrial and Manufacturing Engineering, College of Engineering, The Pennsylvania
State University, University Park, Pennsylvania, United States
2 Department of Mechanical Engineering, College of Engineering, The Pennsylvania State University,
City, Pennsylvania, United States
3 The Applied Research Laboratory, The Pennsylvania State University, City, Pennsylvania,
United States

Abstract

Binder jetting (BJT) has been extensively explored for additive manufacturing of
ceramics due to its ability to create complex structures by processing refractory
and hard-to-machine materials. However, achieving a uniform powder bed with
high packing density while processing ceramics in BJT remains a challenge. This
study systematically examines the role of powder size, powder temperature, flow
behavior, and powder size distribution on powder bed formation and resulting part
properties. Four different alumina powder sizes (1 µm, 5 µm, 10 µm, and 20 µm) were
investigated. Flowability characterizations reveal that 1 µm powder remains poorly
*Corresponding author: flowable at both room and elevated temperatures, while 20 µm powder demonstrates
Guha Manogharan excellent flowability at both temperatures. Smaller powders, especially 1 µm,
(gum53@psu.edu) exhibit around 25% loss in moisture, which results in pronounced agglomeration
Citation: Shahed KS, Groeneveld- at room temperature. Discrete element method simulations were used to identify
Meijer W, Lear M, Schreiber J, the ideal mixing ratio of the bimodal powder using 5 µm and 20 µm powders. For
Manogharan G. Powder spreading
behavior of bimodal ceramics in the bimodal powder, both the simulation and the experiments exhibited a preferential
binder jetting process. Mater Sci deposition of smaller powders in the spreading direction. However, the 5 µm and
Add Manuf. 2025;4(2):025110016. 20 µm powders did not show any preferential deposition in the simulation, but
doi: 10.36922/MSAM025110016
experiments showed preferential deposition behavior. When using bimodal powder,
Received: March 15, 2025 packing density decreases by 7.65% along the spreading direction, which aligns with
Revised: April 19, 2025 an 8.19% drop in part relative density. These findings offer valuable insights into the
effects of bimodal powder distribution for controlling powder bed packing density
Accepted: April 28, 2025
and potentially leveraging spatial density variations for functional applications such
Published Online: May 21, 2025 as biomedical implants, heat exchangers, and gas filtration.
Copyright: © 2025 Author(s).
This is an Open-Access article
distributed under the terms of the Keywords: Additive manufacturing; Binder jetting; Bimodal powder; Ceramics; Powder
Creative Commons Attribution bed density; Powder spreading
License, permitting distribution,
and reproduction in any medium,
provided the original work is
properly cited.
1. Introduction
Publisher’s Note: AccScience
Publishing remains neutral with Ceramics are highly versatile materials with a wide range of applications in biomedical
regard to jurisdictional claims in
published maps and institutional implants, the casting industry, hypersonic devices, nuclear energy, energy storage devices,
affiliations. and catalytic converters. However, due to their brittle nature, ceramics are difficult to

Volume 4 Issue 2 (2025) 1 doi: 10.36922/MSAM02510016