A high-temperature furnace for in situ small-angle neutron scattering during ceramic processing

The design and operation of a new research furnace, optimized for small-angle neutron scattering experiments at a steady-state nuclear reactor with a cold source, are presented. The apparatus enables the study of thermal processing of materials, such as the sintering behavior in ceramics, through the measurement of their microstructural parameters (e.g. pore sizes, pore volumes and pore surface areas) during thermal treatment. Small-angle neutron scattering measurements can be performed in situ in an oxidizing, reducing or neutral environment at temperatures up to 2000 K. Representative data, obtained from the sintering of a silica gel, are presented, including analysis, which offers the first quantitative measure of the evolution of the surface areas, the pore sizes and the pore-size distribution within a real material during densification. (orig.)