Highly dense, transparent α-Al₂O₃ ceramics from ultrafine nanoparticles via a standard SPS sintering

Using discrete, ultrafine alumina, highly dense transparent (71% real in-line transmission, RIT, λ = 640 nm) ceramics were achieved with grain size as small as 260 nm using standard SPS sintering. We show that use of La³⁺ as a dopant greatly reduces sensitivity to the sintering temperatures. Transparent alumina were achieved in a large range of sintering temperatures, 1140°C < T < 1200°C, thus providing better reliability and flexibility into the fabrication of large sintered transparent ceramic bodies