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In process of non-isothermal forging system, phenomenon of
heat transfer plays an important role in metal deformation. The
heat transfer coefficient between die and workpiece, generally,
is not constant and can not be obtained by experiment or other
methods. For the purpose of predicting precisely the shape of
workpiece, it is important to investigate the factors affecting
contact heattransfer coefficient.
In this article, the inverse analysis based on the direct
sensitivity coefficient method is extended to deal with two-
dimensional transient heat conduction problems with mixed
boundary conditions by using Laplace transform and finite
element techniques. It provides a powerful and reliable method
to evaluate the value of contact heat transfer coefficient by
measuring the temperature inside the die. Consequently, the
heat flux through interface and the temperature distribution
inside the workpiece can be completely evaluated.Mechanical
model of this forming processes is then dealt with by using
thermal-viscoplastic analysis and finite element method.
Finally, the distributions of stress, strain, strain
rate and theshape of workpiece inside the workpiece can be
obtained.
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