Design and fabrication of aluminum honeycomb sandwich structures by atmosphere protect brazing: Microstructural evolution and mechanical behavior

Aluminum honeycomb sandwich structures with robust interfacial bonding and great mechanical response were fabricated by atmosphere protect brazing technique. The key brazing parameters (brazing temperature, holding time) were investigated and the correlations between interfacial microstructure evolution and mechanical behavior were addressed. Suitable brazing parameters (600 °C-15 min) could not only minimize the deterioration of high thermal cycle on the performance of joints including grain coarsening and over-burning of core walls, but also provide excellent interface metallurgical bonding. Additionally, the dominant failure mode of brazed aluminum honeycomb sandwich structures was core buckling rather than skin-core debonding. This study provides a reliable and efficient method to enhance interfacial bonding and overall performance of honeycomb sandwich structures. [Display omitted]