The influence of material parameters on the inversion property of 20L near hemispherical metal diaphragm

The numerical model of the near hemispherical metal diaphragm with varying thickness was established according to elastic-plasticity nonlinear finite element method (FEM). According to this model, an orthogonal experiment was designed to study the effects of hardening exponent, yield strength and elastic modulus on the inversion property of 20L near hemispherical metal diaphragm. The largest thickness reduction after inversing Δt_m and the largest deflection angle during the deformation process β_m are used to estimate the inversion property. The results show that the diaphragm can inverse steadily with the elastic modulus larger than 55GPa, yield strength less than 220MPa and the hardening exponent less than 0.12. It also indicates that yield strength is the most important parameter for the inversion property of 20L near hemispherical metal diaphragm, followed by hardening exponent and elastic modulus.