Experimental and numerical investigation of weft-knitted reinforced composite under high velocity impact

This paper is aimed to produce a Kevlar/PP weft knitted composite lamina with high absorbed energy under high velocity impact loading and propose a finite element model for studying the initiation and evolution of interlaminar damage with focusing on the experimental extraction of the required properties for the simulation. In the fabrication procedure, the fabrics produced on a modern flat-knitting machine were being processed via hot-pressure molding technique until the thermoplastic component formed the composite matrix phase. Based on a progressive damage model and using Hashin criterion in composite layers, damage initiation was predicted while the damage evolution was predicted by reducing the value of stiffness based on fracture toughness energy that is available in ABAQUS. Parameters required for modeling such as fracture toughness energy, were experimentally measured through some tests such as compact tension. The proposed model was validated by making comparison between the experimental and numerical results of the impactor velocity before and after the test of 120 J impact loading and 11 percent difference between the experimental and numerical impact results was observed