Demands for efficient energy and time densification processes have recently stipulated the development of rapid sintering methods. In distinction to furnace sintering, the recently introduced blacklight sintering method exemplifies¹ all the advantages of rapid sintering. Extreme processing rates of 200 °C/s provide short sintering times of a few tens of seconds. Furthermore, it is simple to operate as it doesn’t require complex sample holders, sintering dies, or protective atmospheres. Hence, it is suitable for both the rapid prototyping of new materials and large-scale on-demand production of ceramics.

This presentation focuses on the sinterability of widely used ferroelectric ceramics, BaTiO₃, by blacklight illumination from a Xe-flash lamp. The interplay between illuminated energy density, short wavelength absorption and transmission in the material, and the subsequent response of the material in heating up are intriguing and only partially understood. Thus, by carefully choosing Xe-flash lamp parameters, BaTiO₃ powder morphology and compaction percent, a temperature of approximately 1300 °C is reached within the first 10 s. After only 30 s of illumination, the sample is densified up to 90 % of its theoretical density. Furthermore, competitive BaTiO₃ electrical properties are achieved after blacklight sintering, e.g. room temperature permittivity of 5000 and Curie point at 130 °C. Even though all as-sintered samples exhibit a high contribution of leakage current, a post-annealing treatment minimizes this effect, most probably caused by oxygen vacancies. Therefore, this proof of concept verifies the viability of blacklight sintering as a well-suitable method for ferroelectric ceramic materials.

1.    Porz, L. et al. Blacklight sintering of ceramics. Mater. Horizons 9, 1717–1726 (2022).