Production of hollow ceramic rods by SHS extrusion

The possibility of producing hollow ceramic rods from an Al2O3-based material by SHS extrusion was first shown. A mechanism of formation of such rods by die swell was proposed. It was demonstrated that, at high temperatures, the material can have viscoelastic properties. The studies were performed in the system 2B2O3-6Al-2Cr2O3, in which a ceramic material based on aluminum and chromium oxides with strengthening chromium boride particles forms by self-propagating high temperature synthesis and redox reactions.