Adhesive Bonding of Oxide Ceramics for Complex Ceramic Parts in High Temperature Furnaces

Abstract

Within the scope of the project ENERTHERM: Energy efficiency of thermal processes which is funded by the Bavarian Ministry of Economy (BMWi) components and systems for high-temperature are being developed. Monolithic oxide ceramics (mullite, Al2O3) and oxide-fiber reinforced ceramics (O-CMC) show a high potential for high temperature (HT) applications. Additionally, the demand for complex HT-components such as HT-fanwheels for kilns, supporting HT-lightweight structures or hot gas liners increases. In according to the required component design, joining techniques are needed in order to realize such complex geometries. The generated joints were made by using commercial glass solder from the type Al2O3-SiO2-MgO. For realizing the joining process sintering-joining in HT-kilns was used because of the homogeneous temperature distribution. A CO2 laser (wavelength of 10.6 microns and a power of 1.5 kW) was used for rapid joining process. The mechanical properties were determined in according to DIN EN 843-1 and DIN EN 658-3 (4-point bending strength) and evaluated according to Weibull distribution.

Joining oxide ceramic matrix composites by ionotropic gelation

“…In other words, the joining material should be stable at high temperatures (up to 1000°C) and oxidizing atmospheres, too. Commercial glass solders used for joining of oxide ceramics are not suitable for the joining of Ox‐CMCs due to their low interaction with the composite surface 13,14 . Akram et al 6,12 could successfully join Ox‐CMCs using different brazing alloys and tailored glass‐ceramics.…”

“…Commercial glass solders used for joining of oxide ceramics are not suitable for the joining of Ox-CMCs due to their low interaction with the composite surface. 13,14 Akram et al 6,12 could successfully join Ox-CMCs using different brazing alloys and tailored glass-ceramics. The glass-ceramic joints are preferred since they showed higher shear strength and oxidation resistance than the blazing alloys.…”