Hypervelocity Impact Resistant Metal-ceramic Composite Structure Arc Additive Manufacturing Process Method

The composite structure composed of ceramic balls and metal combines high-hardness materials with ductile metals,which has the characteristics of soft,hard interweaving,so that it has good protection performance.It has a key application in the field of tank armor,armed helicopters and shipbuilding and other fields.In this paper,a composite structure of "ceramic ball + high strength steel + stainless steel" is proposed.The design idea of the composite structure and the basis of material selection for each part are described.The ceramic packaging process and additive manufacturing molding process of the composite structure was studied,and the microstructure and performance of each part were analyzed.The composite structure of "ceramic ball + high strength steel + stainless steel" was prepared by adding pre-packaged ceramics,and the hypervelocity impact resistance of the whole structure was analyzed.First,the ceramic metal packaging process was explored,and a more suitable Ag-Cu-Ti solder vacuum brazing packaging nickel-plated Si C process was determined.On this basis,the additive process of the pre-set ceramic and the pre-set package ceramic composite metal structure was compared and analyzed.The microstructure and properties of each part of the metal-ceramic composite structure prepared by the double-wire CMT arc additive pre-packaged ceramic are studied.It was found that after CMT arc addition,Si C ceramic joints will generate more Ti-Ni intermetallic compounds due to continued element diffusion,resulting in a slight decrease in joint shear strength,which is 20.6MPa.The structure of high-strength steel in the backing layer is mainly martensite and bainite,and the structure of stainless steel is mainly austenite.In different sampling directions,the ratio of high-strength steel to stainless steel is quite different,and the corresponding tensile properties are quite different.Under the corresponding sampling rules,as the proportion of stainless steel increases,the impact energy and impact toughness of the back plate layer increase.Finally,the hypervelocity impact resistance behavior and performance of the metal-ceramic composite structure are analyzed.The damage behavior analysis of the backplane layer can better explain the attenuation process of impact kinetic energy and help understand the protective performance of the composite structure.The ultra-high-speed impact behavior process of the composite structure can be divided into three stages: the face layer and the ceramic ball are subjected to impact stress;the broken ceramic and the impact stress act on the back plate layer together;the interaction between the residual impact stress and the back plate layer.It is very important to form effective constraints on ceramic balls in three dimensions.In addition,the arrangement pitch of the ceramic balls has a significant impact on the hypervelocity impact resistance of the composite structure.The protective performance of the composite structure with a ceramic pitch of 4mm is better than that with a ceramic pitch of 6 mm.