Reactive Metal (RM) wrap technology to join ceramic matrix composites (C/SiC and SiC/SiC)

Reactive Metal (RM) wrap technology to join ceramic matrix composites (C/SiC and SiC/SiC)

Description

SiC-based ceramic matrix composites (C/SiC and SiC/SiC) are now extensively used as advanced materials for aerospace and energy applications. They are highly desired in aerospace, gas turbines, nuclear and friction applications due to their low density, high temperature and thermal shock resistance.

Manufacturing of net-shape/ready to use ceramic components (either monolithic or composite) is difficult because of their brittleness and difficult machining process. Joining became a crucial requirement for their advanced applications.

A novel pressure-less joining technique, the “RM-Wrap” (RM = Refractory metals, i.e. Mo, Nb, Ta, etc) has been developed within our research group at Polito, in particular during the PhD Thesis of Dr. Pardeep K. Gianchandani, and has been proven extremely effective to join porous SiC-based composites and foams.

It consists of wrapping Si foils inside a RM wrap in order to prevent molten silicon to leak from the joined area and infiltrate SiC foam and C/SiC during the joining process. It can pressure-less join monolithic ceramics (oxide and non-oxide), ceramic matrix composites (CMC) in a similar (to themselves) and dissimilar configuration, showing excellent reproducibility and short processing route.

The RM-Wrap has a great potential to produce temperature stable oxidation resistant joints (and coatings) able to sustain harsh environments and oxidative environment [1, 2].

Keywords

C/SiC, SiC/SiC, joining, MoSi2, NbSi2, TaSi2

Contact

monica.ferraris@polito.it

Recent reference(s)

[1] P. K. Gianchandani, V. Casalegno, M. Salvo, G. Bianchi, A. Ortona, and M. Ferraris, "SiC foam sandwich structures obtained by Mo-wrap joining," Materials Letters, vol. 221, pp. 240-243, 2018/06/15/ 2018.

[2] P. K. Gianchandani, V. Casalegno, F. Smeacetto, and M. Ferraris, "Pressure-less joining of C/SiC and SiC/SiC by a MoSi2/Si composite," International Journal of Applied Ceramic Technology, vol. 14, pp. 305-312, 2017.

Funding

Project NEXTOWER - Advanced materials solutions for next-generation high efficiency concentrated solar power (CSP) tower systems” (Grant agreement No 721045)