Effects of radius and ratio of radius to thickness on positive expulsion process of metallic spherical-cone diaphragms were numerically analyzed by finite element method (FEM)

and analysis results were verified by several typical samples of radius and ratio of radius to thickness.Numerical results were listed as follows:diaphragms of which the radiuses were too large or too small showed apparent scaling effect

and that of smaller radius was more markable;buckling and post-buckling equilibrium configurations of diaphragms of which the radiuses were from 203mm to 403mm were identical;expulsion efficiency of diaphragms of which the ratios of radius to thickness were too large or too small was low because of weak load-carrying capacity or buckling loads of diaphragms increasing as exponential series along with smaller ratios of radius to thickness respectively.However

expulsion efficiency of diaphragms of which the ratios of radius to thickness were from 160 to 400 was high

and post-buckling equilibrium configurations of those diaphragms showed the same trend.At last

numerical results of typical samples testified the above conclusions.