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Requirements for the cockpit of military vehicles are constantly increasing as a result of escalating threats. The traditional transparent bulletproof armor based on glass have been unsatisfactory to relevant application requirements, and lighter and thinner transparent armor based on ceramics is becoming main option. Similar to other bulletproof armor, the main research fields of transparent bulletproof armor include:seek materials with higher performance for armor components; guide the structure design and ballistic test by experiment or computer simulation; understand the main performance of armor materials, the holistic performance of the armor system and the interaction between the components of the whole system more deeply. Based on this notion, the advantages and disadvantages, preparation technology, development, and application situation of the three kinds of ceramic materials commonly used in transparent armor were summarized. Among the three kinds of ceramics, sapphire has the best static parameters. As for the actual effect of bulletproof, the polycrystalline ceramics are better. The main reason for this phenomenon is that the different fragmentation modes of the two kinds of ceramics lead to the difference of projectile-target interaction effect. After that, the crack growth under high strain rate and bullet-proof property of single crystal, polycrystalline ceramics and glass were discussed. Under uniaxial, high strain rate compression, the crack propagation characteristics of materials are sensitive to impact energy/velocity. Polycrystalline ceramics has a composite failure mode of intergranular fracture and intragranular fracture. Under high energy impact, the damage zone of sapphire is similar to polycrystalline ceramics. Lower than critical energy, some sapphire plate orientations damage would be dominated. Finally, the material selection standards and structural design principles of each functional layer were summarized and prospected. Fine grain polycrystalline ceramic materials with high Young's modulus and high hardness are preferred for the strike-layer. Materials with good fracture toughness, high bending stiffness and the ability to localization of the damage within a narrow region should be selected for the intermediate layer. The materials of backing layer require ductility and low density. The bulletproof efficiency of the transparent-armor systems depends on the type and the degree of interaction/integration of different functional layers.

The surface damage resistance of chemically strengthened aluminosilicate glass is very important. The surface hardness and modulus are closely related to the damage resistance of glass. The micromechanical behaviors such as surface hardness and modulus of chemically strengthened aluminosilicate glass were analyzed by finite element method, and compared with the results of nanoindentation experiment. The results show that the load displacement curve of nanoindentation calculated by finite element method is in good agreement with the experimental results. According to the load displacement curve obtained by finite element simulation, Oliver and Pharr method was used to calculate the hardness and Young’s modulus. The calculated results are very close to the experimental values. The relationship between the yield strength of aluminosilicate glass and the stress-strain in the plastic region calculated by Larsson’s plastic formula is used in the simulation process. The simulation results are in good agreement with the experimental results, which indicates that the accuracy of the plastic parameters of aluminosilicate glass obtained by Larsson’s plastic formula is high. Finally, according to the stress distribution obtained by finite element simulation, the elastic-plastic deformation behavior of aluminosilicate glass before and after chemical strengthening was analyzed. The results show that the surface compressive stress layer produced by chemical strengthening has more influence on the elastic zone of aluminosilicate glass, but has less influence on the plastic zone.

Soda lime/aluminosilicate glass is widely used in commercial and national defense industries due to its excellent physical properties such as high strength and high hardness. Fatigue fracture is one of the main failure modes of glass. Investigating the fatigue behavior is of great importance to its processing, life prediction and failure prevention. In this paper,the fundamental and experimental methods of static fatigue and dynamic fatigue of soda lime/aluminosilicate glass were reviewed.The conclusions obtained by comparing the fatigue behavior of soda lime silicate and aluminosilicate glass demonstrate that the threshold load for radial crack initiation of raw soda lime silicate glass is much lower than raw aluminosilicate glass, the threshold load for radial crack initiation of chemically strengthened soda lime/aluminosilicate glass is increased with the surface compressive stress; the crack growth rate of raw soda lime/aluminosilicate glass increase with fictive temperature and this phenomena is more evident in aluminosilicate glass; the raw soda lime/aluminosilicate glass shows a loading rate-dependent strength while the chemically strengthened aluminosilicate glass does not. Consequently, the effect of different stress state and environment atmosphere on the behavior of static fatigue and dynamic fatigue of static fatigue and dynamic fatigue is an important issue to be studied.