Multi-stage penetration characteristics of thick ultra-high molecular weight polyethylene laminates

To further reveal the failure mechanisms of thick ultra-high molecular weight polyethylene (UHMWPE) laminates, field firing tests were conducted for 10-, 20-, and 30-mm thick laminates against 12.7-mm calibre wedge-shaped fragment simulated projectiles at high velocities between 450 and 1200 m/s. The ballistic performance, deformation process, and staged failure characteristics of the laminates with different thicknesses were compared and analysed. The results demonstrate that the ballistic limits of the UHMWPE laminates increase almost linearly with laminate thickness. The 10-mm thick laminate generally experiences two-stage failure characteristics, whereas three-staged failure occurs in the 20- and 30-mm thick laminates and the progressive delamination is evident. The energy limit concept representing the maximum energy absorption efficiency and the idea of reuse of the thick UHMWPE laminates are proposed in this study. The findings of this research will be useful in the design of flexible and effective UHMWPE-based protective equipment.