Numerical Modeling of Tank Cars Carrying Hazardous Materials With and Without Composite Metal Foam

Large‐scale numerical puncture models are solved for indenter impact on carbon–steel with and without steel–steel composite metal foam (S–S CMF), positioned between indenter and carbon–steel. Metallic matrix of S–S CMF occupies interstitial spaces between hollow steel spheres filled with air, which enhance impact energy absorption and thermal insulation. Numerical models evaluate puncture prevention performance of S–S CMF under large‐scale puncture test simulating impact on pressurized tank car carrying hazardous materials (HAZMATs). S–S CMF is modeled using simplified homogeneous and complex nonhomogeneous fluid cavity approach. Included S–S CMF prevents puncture in carbon–steel plate for parametric analyses involving simulated tank car pressure and S–S CMF thickness. The addition of S–S CMF to carbon–steel plate limits stress triaxiality transformation from dominant tensile to mixed‐mode stress state during impact. CMF prevents puncture by absorbing impact energy and ensuring moderate triaxiality in carbon–steel plate such that void growth and coalescence counteract shear banding. The study reports that 10.91–13.33 mm thick S–S CMF prevents puncture at an indenter velocity of 5.81 m s ⁻¹ and an internal tank car pressure of 689.5 kPa, which otherwise would puncture without the inclusion of CMF. The study indicates the importance of adding CMF layer to tank car structures to improve safety for HAZMAT transportation.