Study On The Preparation Process And Anti-ballistic Properties Of Ceramic Composite Targets Confined By Fiber

Ceramics applied in armor have brilliant properties of high hardness, highcompressive strength and low density so that they have been one of the most importantmaterials in modern armor. However this kind of material is inclined to damage with morethan a few times the original cross-sectional area during the penetration of ceramic-facedtargets, sharply decreasing the effective protection area of armor. Seeking high-strengthfiber cloths to restrain ceramics by adhesion is a popular way for reducing damaged area ofarmor ceramic during the penetration in the domestic and overseas. Owing to technicalreasons of confidentiality, relevant details of the process technology and constraintstructural characteristics of fiber cloths restraining ceramics by adhesion have not beenpublicly reported. This research studied the relationship between the characteristics ofceramic with fiber cloths constraint by adhesion and corresponding ballistic performance inceramic/metal composite armor to provide a scientific basis for the design and structuraloptimization of ceramic composite armor. The main results have shown:(1) For the ceramic/metal composite structure, bonding ceramic wrapped byhigh-strength fiber with metal plate together, the adhesive film with higher film intensityand higher wettability with fiberglass have the greater ballistic performance of compositeplates. Selecting the composite plates with an epoxy type SY-24C (Π type) composite filmwhose bonding strength reaches to40MPa was proved of the highest protectionperformance K and minimum broken areas.(2) The fiberglass composite layer in front of ceramic (front panel) can effectivelyreduce the target plates damaged area. Meanwhile, with the increase of the thickness offiberglass composite material, the protection performance K of composite targets increasesfirstly and decreases soon. The best protective properties can be achieved when thethickness of the adhesive fiber glass is about1mm (2layers of fiberglass clothes). Incontrast, the fiberglass composite layers in back of ceramic (between the ceramic front andmetal back) make few contributions to the protection performance K. Despite the increaseof thickness, K generally increased slowly; However, the fiberglass in back of ceramicenable effectively prevent the abhesion between the ceramic composite plate and the metalback. So it affords a way to further improve the second-strike resistance capability near the crater of the first place. The composite structure with the back glass ceramic compositelayer thickness of1mm (2layers of fiberglass clothes) has the best integrated performance.The bond strength of the ceramic front and the metal back is of great importance on theceramic composite targets, and protection performance K increased by more than9%whenthe high strength of adhesion is40MPa compared with the condition of free overlay.(3) The ceramic composite targets, prepared from the preferred adhesive film, glasslayers and panel/backplane (2layers fiberglass of the front,2layers fiberglass of the back,40MPa strength of the film, Face/back with bonding connection), has the protectionperformance K value of1.43, increased by7%compared with no glass composite structure.What s more, the ceramic composite targets have the small size of the damaged areas.The mechanism is that high-strength fiber bonds the ceramic, metal backplane into a wholethrough the film of high bonding strength, then all of them imposed the lateral constraintson armor-ceramic together. In this case, it can improve the resident ability of ceramic forprojectile, which can prolong the response time of the armor-piercing projectile penetratingceramic pieces so that can improve the protection performance of the composite targets andthe targets integrity after hit by projectile.(4) The experiments explored the ballistic performance of the composite targets,prepared from the front ceramics with high-strength wrapped organic fibers constraint byadhesion and the back steel. The results stated that high-strength fiber can effectivelyprevent broken ceramics pieces from reflectively splashing, and reduce the damaged areasof the ceramic so that this structure can improve the targets integrity after hit; The greaterof the preload wrapped force on fiber, the better of the effect. At the same time, wrappingceramic brings in a soft thick layer (>1.3mm) of fiber between the ceramic and back steel,which makes the support from the back metal to the front ceramics decrease obviously.With the increase of the thickness of fiberglass, the protection performance K of compositetargets drops sharply. Adopting the fiber with high strength, high modulus, small diameterimposing high preload force in the constraints of three dimensions on the faceplate couldreduce the damaged area while improve ballistic performance of the composite targets.