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Abstract: The
researching status on healing condition of internal defect of large
forgings are introduced. To counter the characteristics that the size of
voids are much less than that of ingots. According to St.venant‘s
principle, the shape of voids is supposed to be ellipse shape which is
dealt with easily in mathematics methods. Because the forge of large
forges is done at high temperature, materials have character of
viscosity flow. On
the base of
above-mentioned reasonable hypothesis, for linear viscous materials, the
mechanics relation of fever stress and internal voids of object are made
use of, which appears in the damage mechanics, the analytical equation
which shows the relation of loads and void’s deformation is obtained,
and then the healing mechanics condition of large forgings internal void
defects is gotten. It indicates that stress state affects the close ways
of voids and three-dimensional compressive stress state is the best one
for healing the internal voids of object. This condition makes it
possible straight to calculate deformation of voids by using the loads
and reduction which are shown in hydraulic press, the healing condition
of internal defect become more practicable. The discussions about
different boundary stress and experiments show that the calculating
results is agreeable with results of experiments.
Key words: Large
forgings Forge Healing condition of defect Material processing
Plastic deformation
CLC No: TG316
Received 20050615,received in revised form 20060120
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