Fragment ballistic performance of homogenous and hybrid thermoplastic composites

•We investigated the ballistic efficiency of Twaron®/Dyneema® hybrid composites.•We used low-density polyethylene as the matrix of hot pressed hybrid composites.•Thinner fibers and greater pull-out force of threads led to higher efficiency.•High dense aramid fabrics on the strike face seems to give promising hybrid.•Ballistic limits of hybrids are about the same in the temperature range −60 … +60 °C.

Extensive ballistic tests have been carried out on various protective composites structures up to 900 m/s speed and at elevated and sub-zero temperatures using 6.35 mm steel ball. The ballistic performance was assessed in terms V50 threshold as well as post V50 limit. Multi-layered aramid fabric (Twaron®, RUSLAN®-SVM)/LDPE matrix composite laminates were compared with multi-layered UHMWPE systems based on Dyneema® (HB2, HB80) and with hybrid aramid/Dyneema® HB2, Dyneema® HB2/Dyneema® HB80 laminates. The effect of temperature was observed to be negligible, although brittle behavior resulted in a wide scatter at −60 °C. Laminates based on UHMWPE fibers are much better than others in respect to the values of on indicators of V50 (about 10%) and of the absorbed energy (about 25%) under high-velocity impact conditions. But their energy absorption capability can sharply drop down when projectile's velocity exceeds the ballistic limit.