Study on optimization of nozzle for copper-aluminium clad plate twin-roll cast-rolling

Use Design Modeler and Meshing module of ANSYS Workbench to complete the geometric modeling and meshing of the horizontal twin-roll mill. Combined with the Fluent fluid simulation module, a two-dimensional twin-roll cast-rolling model of a copper-aluminum composite plate and a three-dimensional model of the nozzle structure were established. Through numerical simulation of the cavity structure and end thickness of the casting nozzle, analyzed the influence of the casting nozzle structure on the flow state and outlet velocity distribution of the molten aluminum and the influence of the end thickness of the casting nozzle on the temperature field, liquid phase rate field and flow field distribution in the cast-rolling zone. The results showed that when the narrow inlet type casting nozzle had a spacing of 30 mm between the intermediate dividing block and the adjacent dividing block, the flow distribution of the nozzle cavity was reasonable and the exit velocity was relatively stable. When the thickness of the end of the casting nozzle was 4 mm, the temperature field, liquid phase rate field and flow field distribution of the aluminum liquid were reasonable, which was beneficial to the diffusion and metallurgical combination of copper and aluminum atoms. In order to verify the reliability of numerical simulation method and result analysis, the casting-rolling test was carried out with simulated process parameters. A 10 mm thick copper-aluminum composite plate was obtained by cast-rolling test. The surface was smooth and without wrinkles, and the peel strength was about 85 N/mm. The interface layer consisted of CuAl2 and Cu9Al4 and the peeling surface was torn along the intermetallic compound layer and Al matrix. The optimized nozzle structure had a great shunting effect, which verified the accuracy of the optimized model and the feasibility of the simulation to guide the production, laying a solid foundation for the preparation of high-performance copper-aluminum composite panels. (C) 2020 The Author(s). Published by Elsevier B.V.