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Iron-based amorphous alloys have attracted technological and scientific interest due to their soft magnetic properties. Recently it was found that amorphous alloys like Fe73.5Cu1Nb3Si13.5B9 (FINEMETTM) have a transition to the nanocrystalline state after proper annealing, thus exhibiting excellent magnetic properties. An attempt was made to investigate the crystallization behaviour of this alloy, which is not yet fully known. The investigation was carried out by combining several methods, namely Mossbauer spectroscopy, X-ray diffraction, scanning and transmission electron microscopy as well as microprobe analysis. The alloy was studied after annealing at various temperatures for various times. The corresponding phase analyses are presented. Even after increasing the time of annealing at 950 degrees C from 1 h to 90 h significant changes in the phases were found. It became evident that the question of phase composition can be solved only by a combination of different methods.

This paper deals with the densification and phase transformation during pressureless sintering of Si3N4 with LiYO2 as the sintering additive. The dilatometric shrinkage data show that the first Li2O‐ rich liquid forms as low as 1250°C, resulting in a significant reduction of sintering temperature. On sintering at 1500°C the bulk density increases to more than 90% of the theoretical density with only minor phase transformation from α‐Si3N4 to β‐Si3N4 taking place. At 1600°C the secondary phase has been completely converted into a glassy phase and total conversion of α‐Si3N4 to β‐Si3N4 takes place. The grain growth is anisotropic, leading to a microstructure which has potential for enhanced fracture toughness. Li2O evaporates during sintering. Thus, the liquid phase is transient and the final material might have promising mechanical properties as well as promising high‐temperature properties despite the low sintering temperature. The results show that the Li2O−Y2O3 system can provide very effective low‐temperature sintering additives for silicon nitride.