Engineered composite materials offer broad-spectrum synergistic radiation shielding

Lisa Lock
scientific editor

Robert Egan
associate editor

In a recent breakthrough, Dr. Huo Zhipeng and his student Chen Zuoyang from the Hefei Institutes of 麻豆淫院ical Science of the Chinese Academy of Sciences have developed a new class of PbWO4 filler-reinforced B4C/HDPE composites with tunable microstructures.
By precisely regulating the microstructure of PbWO4 fillers, they achieved enhanced synergistic radiation shielding performance against both neutron and gamma radiation, while elucidating the correlation mechanisms between the microstructure and thermal, mechanical, radiation shielding properties, and service durability of the shielding composites. The results were in Composites Part A: Applied Science and Manufacturing.
The demand for advanced radiation shielding materials has surged with the growing applications in nuclear energy, medical radiotherapy, and aerospace exploration. Neutron and gamma radiation鈥攖wo prevalent and hazardous forms of ionizing radiation鈥攑ose significant risks to human health and sensitive equipment. Conventional shielding materials often fall short, offering limited protection against only one type of radiation or exhibiting poor mechanical integrity and aging resistance.
In this study, by synthesizing PbWO4 fillers with varied microstructures through controlled reaction conditions, the researchers achieved distinct microscopic morphologies such as micron spindle-shaped PbWO4-I, micron spherical PbWO4-II and rough micron spherical PbWO4-III. Among them, the micron-scale rough spherical PbWO4-III filler exhibited superior characteristics such as increased specific surface area, more uniform particle distribution, and better dispersion within the polymer matrix.

This microstructural refinement improved interfacial bonding, leading to enhanced thermal stability, mechanical properties, and ultraviolet aging resistance. Pb and W atoms in PbWO4 fillers effectively absorb gamma photons and fast neutrons, while B atoms in B4C fillers provide high thermal neutron absorption. The resulting composite thus offers enhanced synergistic shielding across a broad neutron energy spectrum and gamma ray.
The optimized PbWO4-III/B4C/HDPE composite achieved a 97.32% shielding rate against 虏鈦德睠f neutrons and 76.43% against 鹿鲁鈦稢s gamma photons at a thickness of 15 cm. These results represent a significant improvement over conventional materials, which typically lack this combination of synergistic shielding and robust mechanical performance.
This work not only demonstrates the importance of microstructure control in composite design but also provides a promising strategy for next-generation, high-performance radiation protection materials, according to the team.
More information: Zhipeng Huo et al, Microstructure regulatable PbWO4 fillers reinforced B4C/HDPE composites for synergistic radiation shielding of neutron and gamma-ray, Composites Part A: Applied Science and Manufacturing (2025).
Provided by Chinese Academy of Sciences