LAUSR

Abstract Sinter-forging is a shaping and densification technique that has fallen into oblivion today. However, the ignorance of this technique is unjustified. It is shown that sinter-forging can be utilized for preparation of transparent magnesium aluminum spinel (MgAl2O4) ceramics in SPS equipment. While the porosity and grain size of the materials prepared via sinter-forging and conventional SPS with the same process schedule is very similar (0.2–1.1 % and 0.33 ± 0.02 µm, respectively) the in-line transmittance (at a wavelength of 550 nm) is 45 % for the material prepared via sinter-forging, but only 3 % for the material prepared via conventional SPS. The reason for this surprisingly high in-line transmittance at relatively high porosity is evidently the pore size, which is much smaller with sinter-forging than with conventional SPS.