Yanis Verkhoshanskiy

Digital light processing (DLP) or stereolithography is the most promising method of additive manufacturing (3D printing) of products based on high-energy materials due to, first of all, the absence of a high-temperature impact on the material. This paper presents research results of an ultraviolet (UV)-cured urethane methacrylate polymer containing 70 wt.% of high-energy solid powder based on ammonium salts, which is intended for digital light processing. Polymerization of the initial slurry is studied herein. It is shown that the addition of coarse powder transparency for the UV radiation to resin increases its curing depth. The thickness of the layer, which can polymerize, varies from 600 µm to 2 mm when the light power density ranges from 20 to 400 mJ/cm², respectively. In DLP-based 3D printing, the obtained material density is 92% of the full density, while the compressive strength is 29 ± 3 MPa, and the ultimate tensile strength is 13 ± 1.3 MPa. The thermogravimetric analysis shows the decrease in the thermal decomposition temperature of UV-cured resin with high-energy additives compared to the thermal decomposition temperatures of the initial components separately. Thermal decomposition is accompanied by intensive heat generation. The burning rate of obtained samples grows from 0.74 to 3.68 mm/s, respectively, at the pressure growth from 0.1 to 4 MPa. Based on the results, it can be concluded that DLP-based 3D printing with the proposed UV photocurable resin is rather promising for the fabrication of multicomponent high-energy systems and complex profile parts produced therefrom.

AlMgB₁₄ materials were obtained by hot-pressing of the prereacted AlMgB₁₄ powder. The phase composition, structure, hardness and flexural strength have been studied. The XRD studies shown that the phase composition of the obtained materials contains from 9 to 12 wt. % of the spinel MgAl₂O₄ phase except target AlMgB₁₄-phase. The spinel content increases linearly with an increase in the hot-pressing temperature from 1400 °C to 1600 °C. It was found that the density of the studied materials non-linearly depends on the hot-pressing temperature. An increase in the hot-pressing temperature from 1400 °C to 1500 °C leads to an increase in the relative density of the samples from 84% to 93%, respectively. A further increase in the hot-pressing temperature to 1600 °C leads to a decrease in the relative density to 81% due to the complication of the densification processes with an increase in the spinel content. An increase in the relative density from 81% to 93% leads to an increase in the flexural strength from 121 to 314 MPa and an increase in the Vickers microhardness from 5.1 to 7.9 GPa, respectively.