Reactive partial transient liquid phase diffusion bonding (R-PTLPB) uses layered filler materials for brazing, which are arranged in a sandwich structure. This structure consists of active element interlayers and a melting point depressing core layer. The reactive PTLP bonding process is applicable to join dissimilar materials (e.g. ceramic- metal-systems) as well as similar materials (e.g. ceramic-ceramic-systems). Additionally, bonds produced with this process offer some special features, such as a re-melting temperature which is higher than the brazing temperature and a good control of the occurring reactions. Hence, these bonds are well suitable for high temperature applications or to bond thermally sensitive materials. In the present study, the reactive PTLP bonding process was investigated and qualified to join a SiC-SiC system. For this purpose, titanium and zirconium were deposited on ceramic surfaces as active interlayers by means of physical vapor deposition (Arc-PVD). Nickel foils were employed as metallic core interlayers. The effects of the active elements on the forming microstructure and the porosity of the brazing zone were investigated at different brazing temperatures and with different holding times.
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