| Z-pins reinforced 2D ceramic matrix composites(CMCs), integratedly designed new materials, are developed to enhance 2D CMCs through-thickness in the form of Z-pins and to ensure significant increase in inter-laminar fracture toughness, delamination resistance and impact resistance, and Z-pins reinforced 2D CMCs have much application. These researches of Z-pins reinforced CMCs are very important and meaningful both theoretically and practically for guiding the design and application of materials.We analyzed the preset depth of cutting through FEM and sheared testing of z-pin reinforced plain weave ceramic matrix composites, distribution of inter-laminar stresses through implantation of z-pin and fixing jig. The results show: the deeper the presented incision depth, the more obvious of stress concentration of the incision around incision, inter-laminar shear strength decreases with the increasing depth of cuts. Bending of the specimen can make stress on the shear plane more uniform.It reduces area of stress concentration of the incision around incision and makes stress distribution of the shear surface uniformly with z-pin. Inter-laminar shear strength of the material enhanced when plain weave ceramic matrix composites was added a certain amount of z-pin.We analyzed process of extraction degumming of z-pin the process of crack propagation between z-pin and Laminates, through double cantilever beam test pieces, establishing DCB test model with ABAQUS software, simulating the matrix cracking with cohesion model. All for the effects of release rate of strain energy between layers in type â… z-pin reinforced ceramic matrix composite. The results say:increasing the z-pin diameter, increasing the number of z-pin unit width of the specimen, reducing z-pin spacing can effectively improve the inter-laminar fracture toughness of type â… z-pin reinforced plain weave carbon / silicon carbide ceramic matrix composite laminates. |
PDF Full Text Request