Designing And Finite Element Simulating Of Ceramic/Composite Lightweight Armor Used For Helicopters

Helicopter is the most important vehicle during the tri-dimensional battle among maritime, terrestrial, spatial, celestial and information-based space, its survivability plays a very important role in the victory of war. The hostile ground forces become more and more severity, so more and more attention should be paid to the study of armor. This paper focus on how to choose proper raw materials and simulated the ballistic properties of composite backing plate and ceramic/composite armor, aiming at the protect ability against 12.7mm hard steel cone projectile with initial velocity of 487 meter per second.In this paper the B4C ceramic was selected as the hard facing plate due to its excellent properties and lower density;And choose immingling fibers of Kevlar and S-2 glass fiber as the reinforce fibers, on account of the fast responses to impact wave. At the same time, Maxwell model was used, which explains the matrix match principle for ballistic composite.In terms of the theory analysis of structure design for composite backing plate, the demands of fiber and resin content and properties are analyzed from energy absorption and complex effect. It shows that increase fiber content based on the integer of fiber and matrix, or enhance modulus of material will improve the transmit velocity of impact wave, therefore more energy will be absorbed, and the ballistic velocity be improved.This paper used MSC.Patran and Dytran software as an analyzing tool to simulate the damage of fiber reinforced polymer composite backing plate, and evaluated its ballistic Performance and optimized its structure. Through appropriate analysis model, finite element calculation, and correct boundary and restriction, residual velocity and energy absorbed by plate been gotten, through which we can evaluate the ballistic properties of target plate. A good level of correlation is observed between the simulated results and the academic ones. Then target with different thickness, different angles between layers, different intermix modality and contents are simulated to optimize the backing plate of the lightweight armor. The simulating result shows that the plate with 50 percent volume of Kevlar and 50 percent of S-2 Glass fiber have the best ballistic properties, the optimized angle is 0°/30°/60°/90°/-60°/-30°, and the best stacking-sequence is alternatively.The typical structure of lightweight armor is with a ceramic hard facing plate and a composite backing plate. By analyzing the response of ceramic and composite plate after impact, correct finite model and effective constitute models be founded. Finite element analyzing software MSC.Patran/Dytran was used to model the impact of projectile to armor. Results showed that 23.51 millimeter ceramic/composite armor can resistant the penetration of 12.7 millimeter caliber flat-node projectile with initial velocity of 487 meter per second, which satisfied the ones leaded by theoretical predictions.