Hairui Liu, Shaohong Liu, Limin Zhou, Hao Cui, Hongying Pei, Wenyan Zhou, Manmen Liu, Haigang Dong, Ming Wen, Li Chen, Wei Wang, Song Li, Jianjun Wang, Liang Zuo
ABSTRACT The thermal expansion mismatch between sapphire and Ti‐6Al‐4V (TC4) alloy has traditionally limited the shear strength of ceramic‐metal joints to ≤ 170 MPa. In this study, active brazing with Ag‐35.25Cu‐1.75Ti (wt%) leads to the formation of a dual‐function microstructure, wherein uniformly dispersed submicron Ti 3 (Cu,Al) 3 O particles embedded in a ductile Ag‐Cu matrix contribute to both Orowan strengthening and reduction in the coefficient of thermal expansion (CTE). Simultaneously, a thin Ti 3 (Cu,Al) 3 O reaction layer forms a coherent interface with sapphire. This tailored microstructure results in an unprecedented shear strength of 218.3 MPa, marking a 29% improvement over previous records. By combining fine‐particle reinforcement, a coherent reaction layer, and mitigation of residual stresses, this approach offers a promising strategy for developing high‐strength ceramic‐metal joints.