Analytical Calculation of Elastic-Plastic Stress in Multilayered Cylinders with Interlaminar Gaps

Currently, with the increasing demands for manufacturing precision and production efficiency, the number of layers and the overall thickness of multilayered clamping high-pressure vessels have dramatically increased. Building upon previous studies in linear elastic calculations, this research takes into account the strain hardening of metallic materials and adopts a bilinear hardening elastic-plastic model. Analytical expressions for the elastic-plastic stress distribution, initial yield pressure pyield, and full yield pressure py of multilayered cylinders with interlaminar gaps are derived. In the derivation process, consistent with prior elastic studies, the calculation method for the equivalent radius Req in the plastic region is proposed. Finite element verification shows that the analytical stress calculation results align well with the finite element analysis, demonstrating the high accuracy of the proposed calculation method.