Based on the structure analysis of alternator poles, two
closed die forging steps in one heat forming process of alternator poles were
put forward, as well as the forming die system. Firstly, a thicker bottom base
of alternator poles was per-formed by radial forging, then the middle boss
and pole claw were forming on the bottom base by backward extrusion. A 3-D
coupled thermo-mechanical finite element model was created. The billet
deformation, metal flow and forming load were obtained. The results showed that
a filling well forging without overlap defects could be obtained by this
process, and that the forming load at the first step increased slowly, but the load
increased sharply at the second step when the middle boss was filling
completely by the former process. An improved process was put forward, which changed the flow mode in the second forging step, it can
considerably reduce the final forging load.
Cite this paper
Yang, C. and Zhao, S. (2013) Research on Combined Hot Extrusion Forming Process of Alternator Poles. Journal of Materials Science and Chemical Engineering
, 16-22. doi: 10.4236/msce.2013.15004
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