Effect of adhesive interlayers on protective performance of bio-inspired building ceramic covering

Abstract

The brick-and-mortar microstructure of nacre is usually considered as a source of inspiration for the development of strong and tough artificial materials. In this article, a nacre-inspired layered-and-staggered structural building ceramic protective covering was fabricated, and the effect of four types of adhesive materials on the ballistic performance of the protective covering was investigated through the ballistic test. The experimental results showed that under the impact of the 7.62-mm ordinary rifle bullet at a speed of 790–820 m/s, the average crater diameter in the concrete targets with protective covering was reduced by 40%–72%, and the penetration depth in the concrete was reduced by 70%–100%, compared with those of unprotected concrete targets. For the concrete targets with protective covering, that adopting the silicone sealant interlayers exhibited a smaller crater area but a maximum penetration depth, while that adopting the epoxy adhesive interlayers showed a larger crater area but a minimum penetration depth. Since the targets with the low-cost polyurethane sealant interlayers presented the smallest crater area and the shallower penetration depth, it can be concluded that the concrete with the protective covering using polyurethane sealant interlayers showed the better projectile impact resistance.