Determination of key parameters of Al-Li alloy adhesively bonded joints using cohesive zone model

The key parameters of the adhesive layer of a reinforcing patch are of great significance and affect the ability to suppress crack propagation in an Al-Li alloy patch-reinforced structure. This paper proposes a method to determine the key parameters of the adhesive layer of adhesively bonded joints in the Al-Li alloy patch-reinforced structure. A zero-thickness cohesive zone model (CZM) was selected to simulate the adhesive layer's fracture process, and an orthogonal simulation was designed to compare against the test results. A three-dimensional progressive damage model of an Al-Li alloy patch-reinforced structure with single-lap adhesively bonded joints was developed. The simulation's results closely agree with the test results, demonstrating that this method of determining the key parameters is likely accurate. The results also verify the correctness of the cohesive strength and fracture energy, the two key parameters of the cohesive zone model. The model can accurately predict the strength and fracture process of adhesively bonded joints, and can be used in research to suppress crack propagation in Al-Li alloy patch-reinforced structures.