Abstract
The chemical and phase transformations of δ-Al2O3 (Saffil) fibres during their infiltration with Mg-8 wt% Li were studied by scanning and transmission electron microscopy, Auger electron spectroscopy, secondary ion mass spectrometry and X-ray diffraction methods. The infiltration experiments were carried out in autoclave under argon pressure at temperatures of 883–908 K and contact times of 4–30 s as well as at 918 K/420 s. During the course of infiltration, lithium penetrates the Saffil fibres and this process is accompanied by the gradual transformation of the tetragonal δ-Al2O3 lattice towards the cubic spinel LiAl5O8 compound, where part of the Li+ ions is probably substituted by Mg2+ No remarkable interfacial zone at the fibre/matrix interface was observed; however, the Saffil fibres became brittle which had been manifested by the occurrence of fragmentation on the metallographically treated fibre cross-sections. The tensile strength (maximum 220 MPa) of the corresponding metal matrix composite clearly decreased with increased infiltration time.
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Kúdela, S., Gergely, V., Schweighofer, A. et al. The δ-Al2O3 (Saffil) fibre degradation during infiltration with MgLi alloy. J Mater Sci 29, 5071–5077 (1994). https://doi.org/10.1007/BF01151099
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DOI: https://doi.org/10.1007/BF01151099