Thermo-mechanical behaviour of ceramic metal brazed assemblies

Vincent Cazajus (1) , Bernard Lorrain (1) , Hélène Welemane (1) , Yann Paranthoen (2) , Moussa Karama (1)

1 LGP - Laboratoire Génie de Production
2 SCT - Société des Céramiques Techniques

This study investigates the effects of residual stresses developed during brazing on the performance of brazed ceramic metal joints. The thermal expansion gradient between ceramic and metallic materials leads to the development of such stresses during the cooling phase of the brazing process, which consequently reduce the strength of these composite structures. Here, the objective is to compare the failure behaviour of various assemblies observed during experimental tests and obtained through numerical simulations. In order to get a representation consistent with the physical mechanisms involved, these simulations must account for the brazing phase giving rise to residual stresses before applying in use solicitations to brazed joints. This paper focuses on the tensile strength of ceramic metal joints, for which two brittle failure modes (within the ceramic or at the interface) are observed during the experimental tests.

Mots clés: Ceramic metal assembly; Residual stresses; Thermomechanical analysis; Experimental tests; Numerical simulations

Domaines: Mécanique des matériaux [physics.class-ph]

Vincent Cazajus, Bernard Lorrain, Hélène Welemane, Yann Paranthoen, Moussa Karama. Thermo-mechanical behaviour of ceramic metal brazed assemblies. Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications, 2008, 222 (4), pp.291-297. ⟨10.1243/14644207JMDA195⟩. ⟨hal-03476871⟩