An elastoplastic energy model for predicting the deformation behaviors of various structural components

Abstract

• An elastoplastic energy model about energy, load, displacement and materials properties is proposed. • For thirteen SCs, the model predictions agree well with the FEA results under linear elastic, fully plastic and elastoplastic conditions. • For cracked SCs, the J - integral vs. load relation is derived and verified based on the EEM. • The model has been applied into materials testing like indentation, small punch test and ring compression etc. Elastoplastic load-displacement relation is widely concerned in material testing. For isotropic-homogeneous and power-law hardening ductile materials, an elastoplastic energy model (EEM) correlating energy, load, displacement and uniaxial constitutive parameters is derived based on equivalent energy principle. An elastoplastic factor λ for engineering superposition of elastic displacement and plastic displacement is introduced and discussed, which makes the model applicable with more structural components (SCs). The model is verified with thirteen SCs used in materials testing and the results show a good agreement between model predictions and calculations from finite element analysis (FEA) under linear elastic, fully plastic and elastoplastic conditions. Some experimental results for ring-compression, spherical indentation and funnel tension are conducted to verify the model and a valid accordance is presented. Additionally, an explicit J -integral – load relation for classic cracked SCs is also derived based on the EEM and a good coincidence is observed during a comparison with results directly from FEA.