A constitutive model for rate dependent and rate independent inelasticity. Application to IN718

A 3-Node Co-Rotational Triangular Elasto-Plastic Shell Element Using Vectorial Rotational Variables

“…In addition, the residual bending flexibility is added to the transverse shear flexibility to improve the accuracy of the element further. For elasto-plastic modeling, the fibre approach which can describe the plastic zone spreading process in shell structures undergoing large elastoplastic deformation [56][57][58][59] is adopted, the Maxwell-Huber-Hencky-von Mises yield criterion for isotropic hardening case [60][61][62][63][64] is introduced, and the material is assumed to be linear hardening. A backward-Euler return-mapping integration algorithm [60][61] is used to trace the yield surface, and a consistent elasto-plastic tangent modulus matrix is employed.…”

“…To exclude the influence of element rigid-body rotations from the local displacement field, a zero-'macro spin' co-rotational framework, which can significantly reduce the rigid-body rotations of infinitesimal segments at different material points within the element domain in an aggregate sense [65], is employed for the present element to simplify the stress-strain constitutive relation. Compared to other existing co-rotational element formulations [61][62][63][64][65][66], the present 3-node triangular elasto-plastic shell element formulation has several features: i) All nodal variables are additive in a nonlinear incremental solution procedure, and as a result, updating the element matrices is simple and efficient; ii) Symmetric element tangent stiffness matrices are obtained in both the local and global coordinate systems, leading to computational efficiency and significant computer storage saving; and iii) The element tangent stiffness matrix is updated using the total values of the nodal variables in an incremental solution procedure, making it advantageous for solving dynamic problems [67][68][69][70]. The present 3-node triangular shell element demonstrates satisfying convergence and reliability in solving elastic and elasto-plastic plate/shell problems undergoing large displacements [36,[71][72][73][74][75][76][77][78][79][80][81].…”

Correlation between crack length and load drop for low-cycle fatigue crack growth in Ti-6242

“…The Ohno-Wang model and the Chaboche with threshold model have been included in this work due to that they are often discussed and used when improved predictions of mean stress relaxation or ratchetting behaviour are needed, see e.g. [8,18,21,22].…”

Constitutive modeling of Aluminum Alloy 7050 cyclic mean stress relaxation and ratcheting

“…Moreover, very limited modeling work has been published on the mean stress relaxation effects under strain controlled histories (e.g. Chaboche and Jung, 1997;Hu et al, 1999;Zhuang and Halford, 2001;Landersheim et al, 2011;Becker and Hackenberg, 2011). Numerous models constructed on the basis of the Armstrong and Frederick (AF) kinematic hardening rule (Armstrong and Frederick, 1966) and its Multi component AF extension (MAF) (Chaboche et al, 1979) have been proposed and employed in an effort to simulate the ratcheting effects under uniaxial and multiaxial loading histories, amongst others by Hassan et al (2008), Chaboche (1991), Ohno and Wang (1993), Jiang and Sehitoglu (1994), Delobelle et al (1995) and Kang et al (2004).…”