Ballistic Tests of Alumina-UHMWPE Composites Submitted to Gamma Radiation

Abstract

The energy absorption in ballistic tests of alumina-ultra high molecular weight polyethylene (UHMWPE) composites with 60, 80 and 90 wt% alumina submitted to gamma radiation doses of 25, 50 and 75 kGy was investigated. The ballistic tests were carried out at subsonic speed using a compressed air system. The results showed that the composite with 80% alumina irradiated with 50 kGy yields the best ballistic results. Gel content, Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results showed that this composite is the one with the highest concentration of crosslinks and the lowest volume fraction of amorphous UHMWPE. Scanning electron microscopy (SEM) images of the same composite showed a high pullout, suggesting that gamma irradiation increases the adhesion between alumina and UHMWPE.

Mechanical and ballistic characterization of high-density polyethylene composites reinforced with alumina and silicon carbide particles

“…The authors observed that fractions of 80 wt% and 85 wt% resulted in the best results of ballistic resistance, in which the penetration of an ammunition caliber .22 LR, was almost null. Figueiredo et al [55] performed ballistic tests with .22 LR ammunition in UHMWPE/Al2O3 composites subjected to gamma radiation at different ratios (0, 25, 50, and 75 kGy). The composites in general showed absorption of ballistic energy around 20% to 30%, results compatible with the present study, however, the addition of 80 wt% Al2O3 and 50 kGy of gamma radiation resulted in the absorption of approximately 65%, resulting in improved ballistic performance.…”

“…Caraschi and Leão [53] found values of hardness around 62, while Koffi et al [54] obtained a hardness of 50.6 Shore D for pure HDPE. With the addition of ceramic reinforcement, the hardness is high, as Al2O3 and SiC have higher hardness than ceramic HDPE, which has a greater hardness than polymeric materials [23,55].…”