Accurate prediction of the ultimate breakage pressure load for pyro-inflator
housing is a critical aspect of inflator development. In this study, the tensile
test of a specimen, from its initial shape to fracture, is simulated to verify
the material properties of the inflator housing. The numerical results
demonstrate high accuracy, with the tensile force–displacement curve, maximum
tensile force, necking in the concentrated instability zone, fracture location,
and inclined angle all closely matching the experimental data. Following
material correlation, the ultimate breakage load of the inflator housing under
hydrostatic burst test conditions is calculated using an explicit solver. A
stress tensor state analysis method is proposed to define the ultimate load
based on the onset of plastic instability in the thickness direction at the top
center of the inflator. Compared to experimental results, the accuracy of the
ultimate breakage pressure prediction using this method is 99.04%, while the
accuracy using the arc-length implicit algorithm is 97.10%. By analyzing the
stress and strain changes in key positions during uniaxial tensile and
hydrostatic burst biaxial tensile tests, this method provides high precision in
forecasting ultimate loads and defining fracture strains. Future work will
investigate dynamic loading effects and machine learning–enhanced instability
criteria, with particular attention to the influence of manufacturing stamping
processes on predictive model accuracy.