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In the field of metal forming, for the purpose of using minimum
energy to achieve the required deformation, rising the working
temperature and reducing the resistance of material deformation
is one of the most popular methods. In order to realize the
deformation behaviors of the material, it is necessary to
discuss heat transfer phenomena and deformation energies. There
are many analytical methods applied to simulate the deformation
behaviors of hot extrusion, such as Finite Element Method, Slab
Method, Slip-line Field Method and Upper Bound Method. In this
study, a 3-D heat transfer model for extrusion of bimetal rod
is developed by combining the Upper Bound Method with the
Finite Difference Method. Generally, in 2-D simulation model of
hot extrusion , the analytical results have not good accuracy
compare with the experimental results especially in the
bimetals of multi-core or in the materials with complex shape.
Using the proposed 3-D model, the informations of the hot
extrusion of multi-core bimetals that of the can be obtained
and the results of 3-D model were compare with the 2-D model,
In order to verify the usefulness of this model, experimetals
under different core sizes, different heating temperatures and
different ram speeds were executed, and the results show good
coincidence with the analytical results.
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