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In this paper, a coupled thermo elastic-plastic finite
element model with3-D sandwiched strip symmetric rolling was
derived. The roller was assumed tobe elastic and the transient
heat transfer was considered. The two differentwoskpiece
materials such as aluminum-mild steel and aluminum-copper
wereconsidered. The effect of the different flow stress
characteristics to stripshape after roller was analyzed, and
the elastic deformation of roller andthermal expansion
amount were calculated to investigate how to improve
thesmoothness of strip surface.
In terms of strip, the large deformation-large strain theory,
the updatedLagrangian formulation (U.L.F. ) and incremental
principle were used in thispaper to develop the 3-D thermo
elastic-plastic analytical model of sandwichedstrip symmetric
rolling. The flow stress was considered as function of strain,
strain rate and temperature.
The binding forces of sandwiched strip were firstly considered
as glued toanalyze the symmetric rolling process with
aluminum-mild steel workpiece.Then, it is conducted a sliding
rule to judge whether the shear stress on thebinding face is
beyond the yield shear stress. If the value of maximum
shearstress is smaller than the yield shear stress, the binding
faces don't slideto each other, otherwise, the reduction rate
was modify in accordance withthis sliding rule.
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