Severe plastic deformation (SPD) methods are developed to produce highly strained materials while 7 experiencing no dimensional changes. Several parameters have to be considered to develop a SPD 8 process such as industrial applicability. In this study, the repetitive corrugation and straightening by 9 rolling (RCSR) method, is used. Process parameters, sample thickness, and rollers design and gap, are 10 optimized according to deformation mode simulated by Abaqus software. The results are verified using 11 DIC (digital image correlation) experiments, which are in good agreement with the simulations. 12 Analytical modeling is also used to estimate accumulated strain after one cycle and the results show a 13 similar trend. Microhardness tests show that deformation homogeneity and hardness are increased 14 after each step of RCSR. 15

The three-layer annular composite sandwich sector plate is investigated numerically using the dynamic relaxation method. The upper and lower faces consist of un-symmetrical rectangular orthotropic laminates, and the core is based on viscoelastic material. The non-linear governing equations are considered using the first-order shear deformation theory and large deflection type of deformation. The constitutive relations of sandwich are presented for laminated faces, and the linear viscoelastic core is considered for the Boltzmann superposition principle. The dynamic relaxation iterative procedure in conjunction with finite-difference discretization is performed for the solution of the governing equations. Under uniform lateral pressure as well as clamped and simply supported edged constraints, the plate deformation is predicted for different times. In order to verify the dynamic relaxation algorithm, the elastic sector plate is compared with finite element solutions, and it is established that the correlations are very satisfactory. The dimensionless deflections, stress resultants, and stress couples of sandwich plates with viscoelastic core are illustrated to show the creep behavior of the plate with an increase in time.