Vacuum Brazing Effect on the Interlayer Failure Behaviors of Elastic-Porous Sandwich Structure with Entangled Metallic Wire Mesh

Abstract

Particular attention has been given to the complexity of the elastic-porous sandwich structure with entangled metallic wire mesh (EMWM), which is a novel rigid-flexible heterogeneous and symmetrical material. The orthogonal experiment design for vacuum brazing was adopted for sensitivity analysis of the key fabrication process on the performances of an EMWM sandwich structure. The shear behaviors of the sandwich structures with different vacuum brazing parameters (e.g., heating rate, brazing temperature, and holding time) were analyzed by mechanical experiments and an interfacial microstructure. The results indicated that the failure behavior of the sandwich structure could be divided into four stages in the mode-I experiment. In addition, the joint quality of the different vacuum brazing process could be shown by the mode-II experiment, and the failure behaviors involves three stages. Additionally, the failure behaviors of the sandwich structure were mainly associated with the deformation of the EMWM core and the strength of the brazing joint. In addition, the relationship between the joint strength and the shear performance of the sandwich structure was revealed through the interfacial microstructure. Furthermore, the importance of the optimized vacuum brazing parameters to fabricate the novel sandwich structure with the best joint performance was demonstrated in this work.