Study on rheological properties of octogen/aluminum-based high viscous cast polymer bonded explosives slurries printable for ultraviolet curing 3D printing

In recent years, the demand for complex heterogeneous energetic materials in explosives and propellants has driven advances in explosive loading technology. UV-curing 3D printing offers a promising approach for fabricating intricate structures. This study focuses on polymer-bonded explosive (PBX) formulations suitable for material extrusion-based UV-curing 3D printing. Through formulation design and rheological analysis, a printable high-viscosity energetic slurry was developed. The optimal formulation—65 wt% HMX, 5 wt% Al powder, and 30 wt% photosensitive binder—exhibited suitable rheological properties: apparent viscosity below 100 Pa·s at 100 s-¹ shear rate, static yield stress between 80–100 Pa, creep recovery difference of 0.00809, a sharp thixotropic peak with minimal loop area, elastic modulus of 107 (10 million), and phase angle below 40°. Using this formulation, a high-precision cylindrical grain and a complex geometric structure were successfully printed. These results demonstrate the feasibility of UV-curing 3D printing for advanced energetic material manufacturing, contributing to progress in additive manufacturing of functional explosives and propellants.