Abstract: Objective The aim is to investigate on dynamic behavior of welded interfaces under complex constraint conditions. Methods Finite element models of brazed joints with three typical interface structures, namely non-interlocking, cylindrical interlocking, and right-angle interlocking, were established with ABAQUS. Mechanical responses under compression, shear, and tensile loads were simulated by applying a transient impact load with an acceleration of 5 000 G in a Split Hopkinson Pressure Bar (SHPB) setup. Results The simulation results indicated that maximum stresses of non-interlocking structure under compression, shear, and tensile loads were 458.5 MPa, 448.2 MPa, and 300.9 MPa, respectively, showing significant stress concentration. Cylindrical interlocking structure improved load distribution through mechanical engagement, with corresponding maximum stresses of 457.6 MPa, 422.8 MPa, and 366.6 MPa. Right-angle interlocking structure exhibited excellent impact resistance due to geometric locking, with corresponding maximum stresses of 458.5 MPa, 463.4 MPa, and 316.7 MPa, but local high-stress zones were observed at the groove edges. Conclusion The interface design decisively influences mechanical behavior of brazed joints under transient load. Both cylindrical and right-angle interlocking structures can effectively reduce stress concentration and improve the overall performance of brazed joints, but potential failure risk at the groove edges of right-angle interlocking structure requires attention. This study provides a theoretical basis for structural optimization design of brazed joints with high reliability.