This master's thesis investigates the influence of strain hardening on the mechanical response of the metallic liner in a type III composite overwrapped pressure vessel, with a focus on the distribution of residual stresses and the structural stability of the liner after unloading. The issue arises from real engineering cases where the occurrence of local buckling in the metallic liner has been experimentally confirmed, but the existing literature does not provide a comprehensive analysis of the effect of strain hardening on the distribution of residual stresses and the possibility of local instability. As part of the thesis, the physical and mechanical properties of the stainless steel liner were experimentally determined, and the measured characteristics were used as input parameters in numerical simulations. The results of the analyses showed that strain hardening has a significant impact on the residual stress distribution after unloading and effectively suppresses the initiation of local structural instability, especially in regions with geometric imperfections such as welded joints.
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