Factors influencing the ballistic impact resistance of elastomer-coated metal substrates

Abstract

An experimental study was carried out of various factors affecting the ballistic penetration resistance of elastomer/steel bilayers. For blunt penetrators, the contribution of the coating to performance is optimized using the hardest substrates, front surface placement of the elastomer, and (when normalizing by added weight) thin, ca. 2–3 mm, coatings. These results, none of which are predicted by existing models, evince the marked coupling of coating and substrate in the impact response of the bilayer. We also show that nanoparticle fillers have a modest effect on ballistic performance of polyurea coatings, changing the penetration velocity by a few percent or less. This contrasts with the linear dynamic mechanical behavior, which shows much more significant increases in energy absorption due to nano-reinforcement.

Keywords:

• ballistic impact resistance
• elastomer coatings
• metal substrates
• polyurea

Acknowledgements

This work was supported by the Office of Naval Research, in part by Code 331. We thank C.B. Giller for the Brinell hardness measurements.