Z-pins Reinforced Carbon Fiber / Resin Bonded Composite Structural Strength Analysis

Carbon fiber / resin matrix composite laminate has excellent properties of high specific modulus, high strength, which are widely used in the field of aircraft skin, pressure tanks, and sports equipment. The composite connection structure, including composite components connection and composite-composite connection, occupies an important position in the composite material structure design. A large number of facts show that the reasonable design of connection design, not only can satisfy the use requirement, reduce the structure weight, and can prolong the service life of the structure. Otherwise, it may cause damage in the joints, and even cause a major accident.Therefore, the composite structure of the bond strength of engineering analysis has very important significance.First by tensile test, the measured laminated plate under uniaxial tensile load-displacement curve, and the fracture morphology was analyzed. Then modelling finite element,use Hashin failure criterion to determine whether the failure unit, and then use the stiffness degradation model to simulate material properties after failure. Finite element analysis indicates that the carbon fiber / resin matrix composite laminates failure mode is mainly fiber tensile failure, tensile failure of the matrix and the tensile failure stratification.Shear strength of Z-pins reinforced carbon fiber / resin matrix composites under uniaxial tension was studied by tensile test. The experimental results showed that:(1)implantation of Z-pins will enhance the shear strength of the structure;(2) under certain conditions, the volume fraction is increased due to the introduction of too much damage, which reduces the shear strength of the adhesive bonded joint;(3) the increase of lap length will significantly increase the shear strength of the structure.We use the finite element analysis method, the establishment of the three kinds of finite element model, using a cohesive zone model to simulate the adhesive degumming process. The strain energy release rate was calculated. Analysis results show that: Implantation of Z-pins and increasing the length of the lap region will increase the ability to inhibit cracking.