| Cu/Al layered composite material, as a high-frequency signal transmission carrier, has been widely used in electric power, machinery, and other fields. There are defects of traditional processes in a long production process and poor combining quality of Cu/Al composites, which limits the large-scale production of high quality interface of composite materials. Therefore, the low-pressure casting-rolling process was chosen to implement the rapid preparation of Cu/Al composites in this article. Low-pressure casting process enables Al, Cu to achieve to instantaneously compositing, intermetallic compounds effectively inhibited. Both the composite slab certain plastic deformation and strengthened metallurgical bonding interface were produced by subsequent rolling. The possibility of the production of large quantities of Cu/Al composite material was provided by rapidly forming advantage of the process.The influence of the different process parameters (liquid aluminum, copper pipe preheating temperature and pressure ratio) on the properties of the composite and Cu/Al interface structure and samples were studied by means of a scanning electron microscope (SEM), X-ray energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), four-probe meter and mechanical property tester mechanical testing apparatus.(1) With the increasing temperature of liquid aluminum, the intermetallic compound layer in the interface transition metal compound layer varies from a single layer to the several layers, and the bonding interface transition layer thickness significantly broadens from 0.5 μm to2.9 μm at the temperature of 680 ℃～760 ℃。(2) The degree of diffusion of Cu and Cu-Al intermetallic compound distribution morphology are significantly influenced by preheating temperature of copper pipe. It is easy for Cu and Al to form a uniform distribution of the intermetallic compound layer at the interface when copper pipes preheating temperature of 250 ℃, and liquid aluminum temperature of 720 ℃. When the copper pipe preheating temperature of 740 ℃, a large number of Cu diffuse, and interact with Al to form plenty of intermetallic compound Al2Cu, Al4Cu9, AlCu and lots of a(Al) solid solution. In addition, Al2Cu diffuses and penetrates to Al matrix side, with a(Al) cross precipitation. At the same time, the brass preheating temperature among 150 ℃～ 350 ℃, the thickness of the transition layer is 1.8～13 um approximately.(3) The thickness and composition of the Cu/Al interface transition zone are significantly influenced by the rolling reduction. When the reduction is 20%, the intermetallic compounds AlCu, Al2Cu and eutectic a(Al)+Al2Cu, constituting the buffer layer has multilayer distribution, and the thickness of the transition layer is about 2.9 μm.When the reduction is 50%, there is the just 0.3 μm interfacial transition layer, a single layer of intermetallic compound layer, and showing a wavy shape distribution.(4) According to the effect of process parameters (liquid-aluminum temperature, preheating temperature of copper pipe and rolling reduction) on mechanical and electrical properties, the optimal parameters, temperature of liquid-aluminum 720 ℃, preheating temperature 250 ℃ and reduction 30%, were determined eventually. XRD analysis results of interface of the Al side and Cu side of the sample under the optimal condition after the peel test show that AlCu, Al2Cu and AICu2 phases generate at Cu interface, and peeling fracture occurs at the Al side, whose transition layer is about 1.8 μm (<2 μm), strengthening the metallurgical bonding interface. During three-point bending test, compound interface deforms collaboratively with the substrate. In addition, the interfacial shear strength of the sample under the optical process condition greater than the strength of the copper cladding layer, the shear fracture occurs at the copper layer, the strength 280 MPa, and a minimum volume resistivity value 2.03×10-8Ω·m.
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