Experimental study of sharp‐tipped projectile perforation of GFRP plates containing sand filler under high velocity impact and quasi‐static loadings

Abstract Penetration and perforation behavior of glass fiber reinforced plastic (GFRP) plates containing 20% sand filler have been investigated via high velocity impact tests using sharp tipped (30°) projectile and quasi‐static perforation tests. Two size sand filler (75 and 600 μm) were used in 4‐, 8‐, and 14‐layered laminated composite plates to study sensitivity of filler size toward loading system. Composite plates were examined for perforation load rate at 5 mm/min and high‐velocity impact loading up to 220 m/s. Results indicated higher energy absorption for GFRP plates containing sand filler for both high‐velocity impact and quasi‐static perforation tests. Higher ballistic limits were recorded for specimens containing sand filler. The study showed clear role played by coarse‐sized sand filler as a secondary reinforcement in terms of higher energy absorption as compared with nonfilled and specimens containing fine‐sized fillers. The investigation successfully characterized behavior of quasi‐static test during penetration and perforation of the sharp‐tipped indenter as an aid for impact application studies. Residual frictional load in the specimens containing sand filler constituted considerable portion of load bearing during perforation in quasi‐static tests. Delaminations followed by fiber and matrix fracture were major failure mode in high‐velocity tests and the main energy absorbing mechanism in thick‐walled plates, whereas in quasi‐static tests the failures were more of matrix fracture and fiber sliding. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers