Modeling the Thermomechanical Behavior of a Metallic Bellows: Case of Stainless Steel 1.4571 and Inconel 718

This study aims to evaluate the thermomechanical stresses to which bellows may be subjected in order to make a judicious choice of the appropriate material for its manufacture and improve its lifespan. To do this, thermomechanical stresses are determined as a function of mechanical and thermal loads. By varying certain geometric and technical parameters, we evaluated the stresses and displacements. We used the State-Space method to determine the state equation and the state matrix in order to numerically determine the intrinsic and extrinsic behaviors of the materials. The different numerical simulations using the finite element method on Abaqus/CAE allowed us to determine the maximum thermomechanical stress for each type of material. The weakening criterion between the mechanical and thermal stresses and the lifespans under thermomechanical stress for the cases of Stainless Steel 1.4571 and Inconel 718 materials are identified and make it possible to choose the material for the manufacture of the metal bellows.