Experimental and numerical investigation on ballistic penetration performance of TC4-Al3Ti layered composites by hot rolling

Laminated composites with a nacreous shell structure can be designed with a high strength but light weight, ideal for protective shields. This work prepared TC4-Al3Ti laminated composite plates by stacking TC4 plates and Al plates with a thickness of 0.5 mm through vacuum multi-pass hot rolling and heat treatment. Their damage morphology and mechanisms, energy absorption capacity, and internal stress distribution were examined through ballistic test and numerical simulations. It is found that the ballistic limit velocity of the TC4-Al3Ti laminated composite is about 486 m/s. After penetration, only craters are formed in the sample without the presentation of fragments, exhibiting excellent performance against multiple projectiles. The failure of TC4Al3Ti laminated composites is dominated by the petal-like damage, i.e., interlayer cracking. Meanwhile, the TC4 layer absorbs energy through plastic deformation, while the Al3Ti layer breaks and produces cracks. This work provides a comprehensive understanding of the damage behavior of the TC4-Al3Ti laminated composite under impact, which could benefit their engineering applications.