高熵钎料制备TiAl/Ni基高温合金接头中半共格界面的强化作用OA

High-strength joining between TiAl and Ni-based superalloy was achieved by reactive brazing using a Ni5Zr5Sn4Cu2Hf2FeCr high-entropy filler.The differences in element properties within the high-entropy system promoted phase separation,while atomic radius compatibility facilitated the widespread formation of semi-coherent interfaces across the joint.The results indicate that these semi-coherent interfaces,through periodic misfit dislocations and their elastoplastic cooperative regulation,effectively relieve residual stresses at the interface,significantly enhancing the mechanical perfor-mance of the joint:the room-temperature shear strength approaches that of the TiAl substrate and remains high at 650 ℃.Atomic-scale simulations and radial distribution function(RDF)analyses further reveal that the thermodynamic separation tendency between Ni and Cr-Mo-Fe-rich phases drives the spontaneous formation of semi-coherent interfaces,providing a key mechanism for the stability of the weld microstructure.This study elucidates the critical role of semi-coherent interfaces in enhancing the performance of high-entropy brazed dissimilar alloy joints and offers new insights for microstructural de-sign in advanced structural material joining.