PSI - Issue 14

C. Praveen et al. / Procedia Structural Integrity 14 (2019) 798–805 C. Praveen et al. / Structural Integrity Procedia 00 (2018) 000–000

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5. Conclusion Plasticity model based on two-internal-variable approach has been successfully implemented into the finite element code in terms of user material subroutine. In this framework, Euler backward implicit algorithm with radial return methodology has been adopted to update the stress state and internal-variables for a given total strain increment. The applicability of the implementation has been demonstrated by simulating the tensile deformation behaviour of type 316LN SS for U-notched specimens with notch radii of 1.25, 2.5 and 5 mm using ABAQUS software. Excellent agreement between predicted and experimental results strongly suggested that the developed material model provides appropriate description of flow behaviour of type 316LN SS. It was observed that the difficulty in spreading of yield zone in the presence of tri-axial stresses leads to higher yield strength of the notched specimen than smooth specimen. Detailed analysis indicated that triaxiality and notch strengthening effect increase with decrease in notch radius. Barlat, F., Glazov, M. V., Brem, J. C., Lege, D. J., 2002. A simple model for dislocation behavior, strain and strain rate hardening evolution in deforming aluminum alloys. International journal of Plasticity 18, 919-939. Christopher, J., Choudhary, B. K., 2015. Kinetics of Uniaxial Tensile Flow and Work Hardening Behavior of Type 316L (N) Austenitic Stainless Steel in the Framework of Two-Internal-Variable Approach. Metallurgical and Materials Transactions A 46, 674-687. Dunne, F., Petrinic, N., 2005. Introduction to computational plasticity. Oxford University Press on Demand. Estrin, Y., Kubin, L. P., 1986. Local strain hardening and nonuniformity of plastic deformation. Acta metallurgica 34, 2455-2464. Estrin, Y., Mecking, H., 1984. A unified phenomenological description of work hardening and creep based on one-parameter models. Acta Metallurgica 32, 57-70. Ganesh Kumar, J., Nandagopal, M., Parameswaran, P., Laha, K., Mathew, M. D., 2014. Effect of notch root radius on tensile behaviour of 316L (N) stainless steel. Materials at High Temperatures 31, 239-248. Hor, A., Morel, F., Lebrun, J.L., Germain G., 2013. Modelling, identification and application of phenomenological constitutive laws over a large strain rate and temperature range. Mechanics of Materials 64, 91-110. Kocks, U.F., 1976. Laws for work-hardening and low-temperature creep. Journal of engineering materials and technology 98, 76-85. Mecking, H., Kocks, U. F., 1981. Kinetics of flow and strain-hardening. Acta Metallurgica 29, 1865-1875. References