Design And Preparation Of New Ceramic Based Composite Protective Armor

In order to solve the current demand for lightweight armor,this paper researched a new method for preparing the metallization surface of Al2O3 ceramic by laser cladding method and using brazing method to connect Al2O3 ceramic with aluminum foam,and the ballistic performance of composite armor was tested.The bullet penetration process was simulated by ANSYS/LS?DYNA simulation program.The influence of ceramic/metal thickness ratio on armor anti-penetration performance was analyzed.The influence of ceramic panel layer,aluminum foam layer and armor outer fiber rope constraint on armor anti-penetration performance was analyzed by bullet penetration experiment.In this experiment,a dense Cu metal layer was prepared on the surface of Al2O3 ceramic by laser beam.During the laser processing,Cu was melted and closely connected with Al2O3 ceramic.The EDS results showed that there was an element transition zone with a width of about 4 ?m at the metallization interface of Al2O3/Cu.When the laser scanning speed is 300 mm/s,the laser row spacing is 0.04 mm,the laser power is 90%of the total power,and the solder paste dosage is 4.8×10-3 g/mm2,the welding interface shear strength of the Al2O3/Al foam soldering interface is 3.05 MPa.The ANSYS/LS-DYNA program is used to simulate the whole process of bullet penetration into ceramic-based composite protective armor.The model and parameters were debugged and the anti-penetration mechanism of protective armor was analyzed.The results shows that the optimum thickness ratio of Al2O3/Al armor structure ranges from 0.57 to 1.5.The five different structure for a total of 14 groups of ceramic matrix composite protective armor were designed and prepared.The bullet penetration experiments were carried out using the 12.7 mm armor-piercing incendiary for 100 m and an all-missile speed at the 208 institute of China ordnance industry.The bullet penetration results show that the F1,F2,F5,F6,F7,F8,F13 and F14 eight kinds of protective armor damage level is level 2 and have excellent anti-penetration performance;The F13 and F14 protective armors with a size of 500×500 mm were hit by multiple bullet strikes,and the results show that both protective armor are resistant to 3 effective bullet strikes(damage level 2).In this experiment,the degree of deformation and deformation area of the protective armor with the aluminum foam layer after bullet penetration is greater than that of the protective armor without the aluminum foam layer,during the process of bullet penetration,the foam aluminum will melt and splash,causing local damage to the backboard.The armor outer fiber rope constraint can effectively increase the shear strength of the Al2O3/Al bonding interface from 2.97 MPa to 7.61 MPa,and also significantly improve the anti-impact strength of the armor internal Al2O3 ceramic.