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Material komposit sangat cocok penggunaanya sebagai bahan balistik karena dari sifat kekakuan dan kekuatan serta densitas yang rendah. Selain itu, penggunaan material komposit akan meningkatkan mass efficiency serta daya tahan untuk jenis kendaraan perang serta protection devices, metode yang digunakan pada saat ini untuk melakukan pengujian ballistic impact berbasis kepada elemen hingga (finite element method) yang merupakan metode penyelesaian dengan membagi objek yang rumit menjadi bagian-bagian yang kecil dan sederhana. Hasil dari metode ini pada permasalahan balistik adalah penggambaran distribusi tegangan-regangan yang terjadi pada pelat komposit. Parameter mechanical properties dalam aplikasi Abaqus CAE, menggunakan pendekatan Johnson-Cook method serta hashin criteria untuk mengetahui damage impact yang terjadi antara proyektil dan pelat komposit. Pada penelitian ini, perforasi terjadi pada pelat graphite/epoxy dan carbon/epoxy dengan jumlah lapisan 15 ply untuk peluru tipe II dan III, sedangkan partial penetration terjadi pada pelat graphite/epoxy dengan menggunakan proyektil tipe II (9mm) pada lapisan ply ke-30, dan untuk proyektil tipe III (44 magnum) terjadi pada lapisan ply ke-72. Partial penetration terjadi pada pelat carbon/epoxy dengan menggunakan proyektil tipe II (9mm) pada lapisan ply ke-42 dan untuk proyektil tipe III (44 magnum) terjadi pada lapisan ply ke-84. Variabel young modulus yang menyebabkan graphite/epoxy lebih stiffness dibandingkan dengan  carbon/epoxy, serta variabel kecepataan yang menyebabkan kerusakan pada pelat dengan jumlah ply yang lebih banyak menggunakan proyektil tipe III (44 Magnum) dengan kecepatan 450 m/s dibandingkan proyektil tipe II (9mm) dengan kecepatan 344 m/s.

           

 

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Composite materials are suitable for use as ballistic materials because of their stiffness and low strength and density. The applications of composite materials will increase mass efficiency and durability for types of war vehicles and protection devices, the method currently used to conduct ballistic impact testing based on finite element method which is a method of settlement by dividing complicated objects into small and simple parts. The result of this method in ballistic problems is the depiction of the stress-strain distribution that occurs on the composite plate. Mechanical property parameters in the Abaqus CAE application, using the Johnson-Cook approach and hashin criteria to determine the damage impact that occurs between projectiles and composite plates. In this study, perforation occurred on graphite/epoxy and carbon/epoxy plates with 15 ply layers for type II and III bullets, while partial penetration occurred on graphite/epoxy plates using type II projectiles (9mm) on the 30^th ply layer, and for type III projectiles (44 magnum) occurring in the 72^nd ply layer. Partial penetration occurs on carbon/epoxy plates using type II projectiles (9mm) in the 42^nd ply layer and for type III projectiles (44 magnum) occurs in the 84^th ply layer. The young modulus variable that causes graphite/epoxy has more stiffness compared to carbon/epoxy, and the velocity variable causes damage to plates with a higher number of ply using type III (44 Magnum) projectiles with velocity 450 m/s than type II projectiles (9mm) with velocity 344 m/s.

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"The use of composite materials with continuous fibers in the aircraft and aerospace industries requires a thorough knowledge of behaviors of these laminate composites under various loading conditions. Indeed, the aim of this work is to simulate linear and nonlinear behavior of a symmetric laminated composite under three-point bending tests. The modelization used is based on an analytical approximation that has been recently developed for isotropic materials. This approximation is still valid for the studied quasi-isotropic laminated composite because it is symmetric with a specific layer sequence. The overall response of laminate composite is determined from the behavior of each ply outside of their orthotropic axis. Two methods are used to calculate the equivalent longitudinal Young-modulus of the laminate. The result shows that when the deflection of the specimens is less than 2.5 times the thickness, the difference between the experimental and analytical curves is about 1% for the average global stresses method, and about 7.5% for the apparent bending modulus method. For large deflections, the difference relative to the first method remains less than 11% and the second method is about 20%."