Optimization of Half-cone Angle of External Mold in Pulling of Fixed Short Rod of Beryllium Bronze Tubing

In virtue of large-scale nonlinear finite element software Marc,the finite element method of two-dimensional axial symmetry elasticity and plasticity was used for analyzing the influence of half-cone angle of external mold on axial stresses,pulling force,friction and axial residual stresses in pulling process of fixed short rod of beryllium bronze tubing.The results indicate that the axial stresses distributing in the beryllium bronze tubing was hardly influenced by the half-cone angle of external mold.But this angle had distinct influence on pulling force.Maximum friction force of the inner and outer surfce both decreased with the increase of half-cone angle of externd mold.When the half-cone angle was 12°or 14°,the pulling force was small and the inner and outer axial residual stresses were also relatively small.Further more,The numerical value difference of residual stresses of the inner surface and outer surface hod only slight change.Quality and precision of beryllium bronze tubing were comparatively fine.Considering different factors,choosing the half-cone angle of external mold of 12° is better than the angle of 14°.The pulling test and simulation were basically consistent with the data.