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Special materials for electromagnetic absorber (EMA) and stealth camouflage techniques are desired due to their widespread applications in the military field. In this paper, BaTiO3/reduced graphene oxide (RGO) composites via hydrothermal process were prepared. BaTiO3 nanotube has unique features: single crystalline, high aspect ratio and uniform distribution on RGO nanosheet. Compared with pure BaTiO3 nanowire, BaTiO3/RGO composites exhibited good absorption properties. The maximum reflection loss (RL) of BaTiO3/reduced graphene oxide (RGO) composites is about of −44.9 dB, and they exhibited an effective electromagnetic absorption bandwidth of 5.4 GHz with the thickness of 2.5 mm BaTiO3/RGO composites could be used as promising materials for EMA and broad absorption properties.

First, [(1-x)MnO2-xMWCNTs] (MMCs) nanocomposites and modified [(1-x)MnO2-xMWCNTs] (mMMCs) nanocomposites were synthesized. Then, novel modified [(1-x)MnO2-xMWCNTs]/waterborne polyurethane (mMMCs/WPU) composites with good microwave absorption properties were prepared by in situ polymerization. The chemical functionalized MMCs and mMMCs nanocomposites were characterized by FTIR and XRD. The structure and properties of the mMMCs/WPU composites were investigated by SEM, TGA, tensile testing, and vector network analyses. The experimental results showed that when the mMMCs nanocomposites were introduced into WPU the thermal stability and tensile strength of mMMCs/WPU composites were improved. When the content of MWCNTs was 20 wt % (where x = 0.2), m[(1-x)MnO2-xMWCNTs]/WPU composites exhibited good microwave absorption properties. The minimum RL value can reach −28.7 dB at 6.4 GHz with a thickness of 2.5 mm. The mMMCs/WPU composites have good thermal stability and tensile strength, which could be used as promisi...

Based on the finite element analysis and fracture toughness test data, this paper verifies the improved Ritchie-Knott-Rice (RKR) local failure criterion using 16MnDR ferritic steel for cryogenic pressure vessels. This criterion's applicability to 16MnDR was verified to verify fracture toughness's different influence factors in the ductile-to-brittle transition temperature (DBTT) region, such as specimen thickness (TST) and temperature. The results indicate that the (4δt, σ22c) criterion applies to 16MnDR steel and effectively transfers the minimum Jc value between samples of different temperatures and thickness.