The R&D team of Protech published a paper online titled "Bulletproof performance and bulletproof mechanusm of interlaminar hybrid composite armor plate" online in the Chinese core journal Acta Materiae Compositae Sinica on June 13th, 2018.

In this paper, the steel core projectile was used to penetrate interlaminar hybrid composite armor plate to explore the bulletproof performance and bulletproof mechanism. The types of hybrid reinforcement with unidirectional (UD) structure were Ultra High Molecular Weight Polyethylene (UHMWPE) fiber and Para-aromatic polyamide fiber, whereas the resin was one of Waterborne Polyurethane (WPU) and Epoxy resin (EP). The effects of hybrid ratio, strike face and resin matrix on ballistic properties were discussed. Also, the fracture morphologies were observed by the stereomicroscopy. Moreover, the failure mechanisms of hybrid composite subjected to the ballistic impact were analyzed. The results showed that the bulletproof performance of hybrid composite armor plate is superior to that of the single fiber reinforced composite armor plate, and the bulletproof performance of WPU is superior to that of EP. Furthermore, when UHMWPE fiber composite worked as strike face, the bulletproof performance is better. Finally, we can concluded that the tensile deformation of fiber and the delamination are the major ways of the absorbing energy under the ballistic impact by the steel-core bullet.