Abstract:The laminated heterogeneous configuration design was applied to improve the strength and toughness of the Cu -Be alloy. The Cu -Be/Cu laminated heterogeneous composite by vacuum hot pressing bonding, hot rolling and subsequent heat treatment was successfully prepared. The microstructure, microhardness and tensile properties of the composites were investigated. During the plastic deformation of the composite, the microstructure evolution, strain distribution and fracture behavior of different metal layers were characterized by in -situ tension under SEM combined with DIC technique. The results show that the Cu-Be/Cu laminated heterogeneous composite is composed of coarse grained Cu layers (with average grain size of 115.3 μm) and fine grained Cu-Be layers (with average grain size of 17.4 μm). The microhardness of Cu-Be layers is approximately 5 times higher than that of Cu layers. The ultimate tensile strength of the composite is between that of the two metals, but theductility of the composite is close to that of the Cu, which is much higher than that of the Cu-Be alloy. During the plastic deformation of the composite, the strain of the Cu-Be layers is mainly coordinated by grain rotation, while the strain of the Cu layers is mainly coordinated by single slip inside the grains. At the initial stage of plastic deformation, the strain concentration first appears in the vicinity to the Cu-Be/Cu interfaces. Then the strain concentration can be transmitted into the metal layers through the interfaces. During the fracture of the composite, the microcracks initiate at the grain boundaries of the Cu-Be layers and propagate along the grain boundaries. Significant crack deflection phenomenon occurs when the cracks propagate to the Cu-Be/Cu interface. The crack propagates transgranular in the Cu layers. The morphology of the fracture of the Cu layer present the characteristics of quasi-cleavage fracture.