Superalloy thin-walled structures are achieved mainly by brazing, but the deformation process of brazed joints is non-uniform, making it a challenging research task. This paper records a thorough investigation of the effect of brazing parameters on the microstructure of joints and its mechanical properties, which mainly inquires into the deformation and fracture mechanisms in the shearing process of GH99/BNi-5a/GH99 joints. The macroscopic-microscopic deformation mechanism of the brazing interface during shearing was studied by Crystal Plasticity (CP) and Molecular Dynamics (MD) on the basis of the optimal brazing parameters. The experimental results show that the brazing interface is mainly formed by (Ni, Cr, Co) (s, s) and possesses a shear strength of approximately 546 MPa. The shearing fracture of the brazed joint occurs along the brazing seam, displaying the characteristics of intergranular fracture. MD simulations show that dislocations disassociate and transform into fine twinning with increased strain. CP simulated the shear deformation process of the brazed joint. The multiscale simulation results are consistent with the experimental results. The mechanical properties of thin-walled materials for brazing are predicted using MD and CP methods.

Multi-component high-entropy alloys (HEAs) have intrigued intensive attentions in the metallic materials fields due to their unprecedented properties including excellent radiation resistance, exceptional strength-ductility synergy at cryogenic temperature and good high-temperature stability. As such, HEAs are promising candidates for many engineering applications in extreme environment. To promote the fabrication and application of HEAs, exploiting HEAs-brazing technique is indispensable due to its cost-effectiveness, simplicity and excellent adaptability to sample configuration. Besides, owing to high-entropy and sluggish diffusion effects, HEAs also can be used as brazing filler metals in the brazing technology. The short review first discusses the brazing of HEAs with different fillers, and the interfacial microstructures and joining properties are summarized. Subsequently, the brazing of traditional ceramics to themselves or to metals with novel HEA filler metals is introduced. Besides, the summary and expectation of the coming research topics are also listed in the conclusions.