The Research On The Key Technologies Of Cladding Strip Continuous Casting Process Using A Twin Roll Caster

As an important product of bimetal composites materials, bimetal composite boardsare widely used in aerospace, Power electronic, chemical industry, shipbuilding andautomobile fields. In recent years, continues casting and rolling technology, with thecharacteristics of low energy cost, short flow path and easier to achieve continuousproduction, has gradually came into view and now becomes a new important way ofproducing the bimetal composite boards. However, compared with those already relevantmature composite technology like rolling composite and explosion composite, this newtechnology still has lots of key techniques that need to be addressed. Based on traditionaltwin roll casting-rolling process, this paper proposes "bimetal composite boards/stripflexible continues casting-rolling process " and the process from flow distributor toproduct was simplified into three separate sections, using numerical simulation method forresearch.I. Flow Distributor part: in order to solve special conditions of flow distributordesigning and decoration, a flow distributor with characteristics of on-line heating andheat preservation was self-made. And based on CFD theory, FLUENT software was usedto calculate the flow coefficient of distributor liquid under the action of gravity.II. copper/aluminum metal liquid solidification after touching the roller: by usingMarc software for secondary development, establishing the finite element model for theprocess of copper/aluminum liquid when flowing out the distributor and getting contactwith casting roller, key location temperature change rule in the copper/aluminum metalliquid solidification process, under the coupled action of multiple factors like roll diameter,the casting roll linear velocity, distributing thickness, angle of the location, the pouringtemperature of molten metal etc., was analyzed and a one-dimensional unsteady heattransfer model was built to quickly calculate key location’s temperature with finitedifference method.III. Copper/aluminum composite rolling part: by using Marc software for secondarydevelopment, establishing the copper/aluminum rolling thermodynamic coupling model,temperature conduction rule was analyzed in the double metal composite rolling process under the coupled action of multiple factors like copper boundary temperature, aluminumboundary temperature, copper initial volume fraction, total deduction ratio and roll gapetc., and put forward that under appropriate process conditions, in the composite surface,aluminum " local remelting" phenomenon will form instantaneous liquid phase transition,which is beneficial to enhance the composite interface strength. Furthermore, the influencerelationship of different total deduction ratio to copper/aluminum deformation distributionwas studied and by adopting the velocity ratio concept, the process conditions ofeliminating warped agio phenomenon are discussed.And then under existing experimental conditions, with low melting point of purealuminum and aluminum alloy as a raw material, the research was finished on thehomemade double roller continuous cast-rolling machine and produced one400mm longdouble metal composite slab.