Experimental and numerical investigations of the effect of cellular wired core on the ballistic resistance of sandwich structures

Sandwich structures usually are of particular importance in different industries including aerospace, marine and automotive due to their high performance and high energy absorption. In this research, the ballistic limit velocity of sandwich panels with wired core and aluminum face-sheets in normal impact with flat head cylindrical projectile has been investigated numerically and experimentally. It was also evaluated the effect of wire diameter and type of layout on the ballistic limit velocity of the panels. The diameter of wires was 4.44, 6, 8 and 10 mm and they were applied as core in 7 types of different layouts. Flat head steel projectiles with mass of 8.6 grams, diameter of 8 mm and length of 22 mm were impacted on the targets at velocities of 250-450 m/s. Results of this research showed that for the panels with the same mass, firstly, the ballistic limit was increased by reducing the wires diameter and increasing the number of their rows; secondly, reducing the distance between the wires also led to increase in ballistic limit and thirdly, the ballistic limit velocity of sandwich panel showed 45% increase with respect to a single-layer target with the same type and mass.