| The 4004 aluminum alloy has been widely used in brazing foil and 434 composite foil due to its good welding performance and fluidity.Nowadays,the alloy is mainly produced by hot-rolling with high production cost and high energy consumption.Twin-roll casting is the most economical way to produce 4004 aluminum alloy sheets.The cold-rolling performance of 4004 aluminum alloy is poor for its high contents of Si,which will lead to the coarsening of Si phases in the twin-roll cast sheets and will also dissever the matrix of alloy.Therefore,it is obviously realistic significances and economic efficiencies to study the production technology of 4004 aluminum alloy by twin-roll casting.In this paper,the effect of the content of Strontium and the annealing parameter on micro structure and cold-rolling performance of twin-roll casting 4004 aluminum alloy is investigated,got the following conclusion:(1)The experiment proved that the 4004 alloy sheet with good quality can be gotten by twin-roll casting,when the thickness of plate is 5.5mm,the pouring temperature is 630? and the casting speed is 1.1m/min.(2)Strontium can change the distribution of ?-Al in the matrix and the morphology of eutectic silicon,and makes the morphology of eutectic silicon turn from coarse flake-like or needle-like into mellow rod-like and worm-like.And the distribution of ?-Al and eutectic silicon in the matrix will also become homogeneous at the same time.Under the experimental condition,the modification effects rise at first and then reduce with the increasing of the Sr contents.The best modification effect is reached at the Sr content is 0.02%.(3)The annealing treatment can spheroidize the eutectic silicon,connect the independent ?-Al,and improve the cold-rolling performance of alloy.(4)In the condition of experiment,the best cold-rolling performance of 4004 alloy plate is obtained when the Sr content is 0.02%,and annealing time is hours,and the reduction of cold rolling is 25%at the same time. |
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