Interface evaluation on the brazed system of AlN‐Ticusil‐Graphite

Abstract The graphite‐Ticusil‐AlN system was joined under vacuum or flowing atmospheres, such as 5% H ₂ ‐95% N ₂ and argon atmosphere, to investigate the morphology and forming mechanism of the reaction phases at the interfaces of AlN‐Ticusil‐graphite layers. Scanning electron microscopy, energy‐dispersive spectroscopy, electron probe microanalysis, and transmission electron microscopy were used to examine the composition and structure of the interface products. The AlN‐Ticusil interface could be divided into two layers, the TiN layer and titanium‐copper–rich compound layer. The thickness of the TiN layer was only affected by the joining temperature and could be regarded as mainly dependent on the reaction. The titanium‐copper compound layer was composed of (Ti,Cu,Al) ₆ N column when joined under vacuum and was composed of TiN particles when joined in a flowing atmosphere. The products on the graphite‐Ticusil interface were also examined as TiC, which was strictly bonded with graphite and Ticusil filler.