Samenvatting
Currently, ballistic helmet shells are made of a single layer (typically composite material)
offering good protection against fragments but only limited protection against small calibre projectiles.
However, nowadays, due to changes in the type of warfare and the desired higher standard of
protection, an improvement of the ballistic protection offered by helmets is required. When designing personal ballistic protection, two important parameters have to be taken into account: areal density and back face deformation. The areal density will determine the total weight of the system, whereas the back face deformation will be related to the possible injuries suffered by the protected individual. For this research, different layered configurations of armour materials were tested in order to determine the feasibility to increase the protective capability of the helmet. These new configurations have been subjected to ballistic testing in order to determine the maximum back face deformation and to identify the optimum layering sequence. As this first phase was only a feasibility study, the ballistic testing concerned flat panel testing only. All configurations used an ultra-high molecular weight poluethylene
composite material (UHMWPE Dyneema® HB80) as the main energy absorbing material. Firstly, the back face signature of the UHMWPE plates has been studied as a function of impact velocity for two different thicknesses. The dynamic deflection was measured using digital image correlation (DIC) techniques. Secondly, the influence of the standoff between the plates and an aluminium final stopping layer (for limiting the back face deformation) was also determined. Finally, the ballistic resistance of the UHMWPE plates with and without an additional low-density polyurethane foam layer was determined. Corresponding numerical models (LS-DYNA finite element models) were also developed and validated, including a detailed numerical study on the behaviour of the UHMWPE Dyneema® HB80 material.
offering good protection against fragments but only limited protection against small calibre projectiles.
However, nowadays, due to changes in the type of warfare and the desired higher standard of
protection, an improvement of the ballistic protection offered by helmets is required. When designing personal ballistic protection, two important parameters have to be taken into account: areal density and back face deformation. The areal density will determine the total weight of the system, whereas the back face deformation will be related to the possible injuries suffered by the protected individual. For this research, different layered configurations of armour materials were tested in order to determine the feasibility to increase the protective capability of the helmet. These new configurations have been subjected to ballistic testing in order to determine the maximum back face deformation and to identify the optimum layering sequence. As this first phase was only a feasibility study, the ballistic testing concerned flat panel testing only. All configurations used an ultra-high molecular weight poluethylene
composite material (UHMWPE Dyneema® HB80) as the main energy absorbing material. Firstly, the back face signature of the UHMWPE plates has been studied as a function of impact velocity for two different thicknesses. The dynamic deflection was measured using digital image correlation (DIC) techniques. Secondly, the influence of the standoff between the plates and an aluminium final stopping layer (for limiting the back face deformation) was also determined. Finally, the ballistic resistance of the UHMWPE plates with and without an additional low-density polyurethane foam layer was determined. Corresponding numerical models (LS-DYNA finite element models) were also developed and validated, including a detailed numerical study on the behaviour of the UHMWPE Dyneema® HB80 material.
Originele taal-2 | Engels |
---|---|
Titel | Personal Armour Systems Symposium 2014 |
Plaats van productie | Cambridge / UK |
Aantal pagina's | 10 |
Status | Gepubliceerd - 2014 |