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DOE OSTI · 3002054

Warpage-Resistant, Under-Extrusion-Free, High-Surface-Quality Additive Manufacturing Process for Polyethylene-Based Composite Radiation Shielding Material

Xu, Duo [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)] (ORCID:0009000636307997)·Korolovych, Volodymyr [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)]·Lyu, You [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)]·Aslarus, Jacqueline [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)]·Flores-Hernandez, Domingo R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Tecnológico de Monterrey (Mexico). Escuela de Ingeniería y Ciencias (EIC)]·Pajovic, Simo [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)] (ORCID:0000000274973118)·Heller, William T. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000164562975)·Sihver, Lembit [University of Texas Rio Grande Valley, Edinburg, TX (United States)]·Boriskina, Svetlana V. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)] (ORCID:0000000167988082)
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Abstract

Polyethylene (PE) is one of the best shielding materials for primary space radiation due to its high hydrogen content. For effective secondary neutron shielding, boron-rich fillers are incorporated to enhance performance. The semicrystalline nature and high thermal expansion coefficient of PE impede its adoption for in situ additive manufacture in space via the fused deposition modeling (FDM) 3D printing. Here, we developed an optimized PE blend to mitigate the effects of under-extrusion and warpage. Guided by studies on extrusion and warpage, we developed an optimal set of printing parameters for the proposed PE blend. The optimum PE blend─both in its pure form and when doped with fillers─has been tested on different FDM printers. The printed structures exhibit high and uniform density, smooth surfaces, no warpage, and competitive mechanical properties. The FDM-printed plates demonstrate efficient shielding from thermal neutrons, predicted via modeling and confirmed experimentally using extended Q-range small-angle neutron scattering.

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additive manufacturingfused deposition modeling (FDM)in-space manufacturingpolyethylene compositesradiation shielding

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Xu, Duo [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)] (ORCID:0009000636307997), Korolovych, Volodymyr [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)], Lyu, You [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)], Aslarus, Jacqueline [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)], Flores-Hernandez, Domingo R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Tecnológico de Monterrey (Mexico). Escuela de Ingeniería y Ciencias (EIC)], Pajovic, Simo [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)] (ORCID:0000000274973118), Heller, William T. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000164562975), Sihver, Lembit [University of Texas Rio Grande Valley, Edinburg, TX (United States)], Boriskina, Svetlana V. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)] (ORCID:0000000167988082). 2025-09-16. Warpage-Resistant, Under-Extrusion-Free, High-Surface-Quality Additive Manufacturing Process for Polyethylene-Based Composite Radiation Shielding Material. https://doi.org/10.1021/acsapm.5c02057

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