In this paper, bismuth oxide (Bi2O3) as the main functional powder, lead (Pb) and tantalum (Ta) as the metal additives, epoxy resin as the matrix and polyester–cotton blended woven fabric as the substrate, Bi2O3 coating nuclear radiation protection composite, Bi2O3/Pb coating nuclear radiation protection composite, and Bi2O3/Ta coating nuclear radiation protection composite with different process parameters were prepared. The cross-section scanning analysis and the influence factor analysis of γ-ray protection performance were carried out, and the mechanical properties of the composites were discussed. The results show that an increase in Bi2O3 content (mass fraction) and an increase in coating thickness can improve the shielding rate of the composite materials to γ-rays. When the thickness of the coating is 1.6 mm and the content of Bi2O3 is 50%, the shielding rate of the composite to γ-rays (at 59.5 keV) reaches 46.1%. The shielding rate of the composite can be increased by adding appropriate metal additives, and the effect of adding Ta is better than that of Pb. The shielding rate of the composite to γ-rays (59.5 keV) can be increased from 28.4% to 31.5% by adding 5% Ta. An increase in Bi2O3 content (mass fraction) and an increase in the coating thickness can aggravate the agglomeration of functional particles in the material. The addition of metal additives can reduce agglomeration to a certain extent. Bi2O3 content, coating thickness, and metal additives all have an effect on the mechanical properties of the composite. If the coating is too thick or the functional particle content is too high, the tensile strength and elongation at break of the composite will be reduced.

Aiming at poor noise reduction performance of light and thin fiber aggregate materials, the polyurethane/ferroferric oxide/activated carbon fiber felt coated flexible composite materials were prepared by coating composite method. The effects of composite structure, ferroferric oxide particle content (10–25%), and coating thickness (0.25–1 mm) on the composites' sound absorption and sound insulation properties were systematically studied. The results show that with the increase of coating thickness and ferroferric oxide particle content, the sound absorption curve of the composite obviously moves to low frequency, and the resonance frequency decreases. When the particle content increased from 0% to 20%, the resonance frequency shifted 967 Hz. When the ferroferric oxide content is 25%, the maximum sound absorption coefficient and maximum transmission loss of the composite are 3.5 times and 25 times of that of the fiber felt, respectively. When the polyurethane/ferroferric oxide film thickness is only 0.1 mm, the maximum sound absorption coefficient and the average sound absorption coefficient of the composite are 3.5 times and 2.3 times of those of activated carbon fiber felt, respectively. Compared with single fiber felt, the composite material has better sound absorption, sound insulation, and mechanical properties while maintaining the thin and soft characteristics of the fiber felt.

Aiming at the difficulty of designing flexible shielding materials for lightweight and complex structures, the radiation shielding simulation model of coated fabric was established by SuperMC nuclear simulation software system and the γ-ray shielding performance of the material was predicted. Pb and Ta doped Bi/PU coated fabric composites were prepared by coating process. SEM, EDS, γ-ray shielding performance, mechanical properties, and wear resistance were tested. The results show that the simulated values of shielding performance are in good agreement with the measured values, the maximum deviation of the predicted value is 2.94% and the minimum is 0.25%. Doping Pb and Ta can increase the probability of the photoelectric effect and improve the γ-ray shielding performance of the material. When the doping amount of Ta is 5wt%, the shielding rate (simulation value) of Bi/Ta/PU coated fabric composites to 59.5 keV, 122 keV, and 184 keV γ-rays reaches 29.80%, 20.35%, and 8.09%, respectively, which is 3.13%, 2.32%, and 0.95% higher than that without doping. However, Ta is more environmentally safe and can replace Pb as a shielding additive. Doping auxiliary functional particles will improve the shielding performance but will reduce the material’s wear resistance and mechanical properties. After doping 5%Ta, the wear resistance index decreased by 6.81, and the tensile strength decreased by 4.5 MPa. The influence mechanism of process parameters on shielding performance is further revealed by visual analysis, which provides a new reference for the design of lead-free flexible shielding materials.

The radiation shielding simulation model of coated fabric (flexible composite) was established for the first time by SuperMC nuclear simulation software to help solve the problems of small volume, complex structure, and difficult design of flexible shielding materials, and the γ-ray shielding performance was calculated. Bismuth/polyurethane coated fabric was prepared by a coating method, and its scanning electron microscope, γ-ray shielding performance and mechanical properties were tested. The results show that the simulation accuracy was improved due to the one-to-one correspondence between the structural parameters and performance parameters of the simulation model and the actual samples. The simulation value was in good agreement with the measured value. The shielding performance and mechanical properties of fabric composites were improved after coating. Increasing the content of bismuth and coating thickness can improve the shielding performance of the coated fabric. However, when the content of bismuth was too large, or the coating was too thick, the mechanical properties were relatively decreased. The deposition of ray energy in the material was analyzed by the visual analysis method, and the influence mechanism of process parameters on shielding performance was further revealed, which provided a new theoretical reference for the design of flexible shielding materials. A shielding material design and performance prediction method based on SuperMC is proposed, which can be used for personalized customization design and performance prediction and evaluation before use. It has practical guiding significance for producing and manufacturing flexible fabric shielding materials for protective clothing and equipment.