Papers by Keyword: Thermo-Mechanical Loadings

Abstract: In AIRBUS, most of the complex shaped titanium fairing parts of pylon and air inlets are produced by superplastic forming (SPF). These parts are cooled down after forming to ease their extraction and increase the production rate, but AIRBUS wastes a lot of time to go back over the geometric defects generated by the cooling step. This paper investigates the simulations of the SPF, cooling and clipping operations of a part on Abaqus^® Finite element software. The different steps of the global process impact the final distortions. SPF impacts the thickness and the microstructure/behavior of material, cooling impacts also the microstructure/behavior of material and promotes distortions through thermal stresses and finally, clipping relaxes the residual stresses of the cut part. An elastic-viscoplastic power law is used to model material behavior during SPF and a temperature dependent elastic perfectly plastic model for the cooling and clipping operations.

Abstract: A bimaterial structure composed of two elastic plates bonded together by an interface with a normal (transverse) crack in the first plate and subjected to monotonically temperature and tension loading is considered. The interface is assumed to exhibit brittle failure at critical shear stress value or progressive damage in a cohesive zone preceding delamination. Using modified Shear lag model, the analytical solution is provided specifying the length of debonding. The critical lengths of a partial debonding along the interface are calculated and the limit value of temperature at full debonding is obtained. The analytical predictions are compared with experimental data and numerical results of Lemaitre and Song. The comparison shows a good agreement and proves the validity of the model used.

Abstract: The finite element model of coupling the thermal field with structural analysis is proposed in order to analyze the thermo-stress of casting ladle structure. The thermal fields of casting ladle with refractory lining structure are computed according to the thermal properties of materials and boundary conditions. Numerical simulation shows that that computed outer temperatures of casting ladle agree with measured ones. The thermo-stress of casting ladle structure is simulated by taking thermal loadings as the loading conditions of the steel shell structure. Material behaviors were described by the Drucker–Prager plasticity model and Von Mises yield criterion. Calculation results of thermo-stress fields shows the outer shell structure is safety under the action of thermal loadings.