PSI - Issue 14

Pankaj Kumar et al. / Procedia Structural Integrity 14 (2019) 96–103 Author name / Structural Integrity Procedia 00 (2018) 000 – 000

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In simulation, one end of the computational domain is fixed and the other end is displaced with same magnitude as obtained during tensile test. The simulated tensile curves are shown in Fig. 1 for both conditions of alloy. In present simulation the ultimate tensile stress (UTS) value is considered as crack initiation criterion during XFEM simulation. Some of the load-elongation history data points (maximum 15 points) are used as input for the simulation. Accordingly, the plastic straining along with classical nucleation and coalescence of cavities for the crack forms till it attains its UTS value. Once material reaches its ultimate tensile strength, crack initiated near gauge section is depicted in enlarged view of computational result shown in Fig. 7. The stress distribution is higher for ACR alloys which signify that it has higher resistance towards fracture. The experimental results depict that ACR alloys fails in more ductile manner as compared with CR alloys. This phenomenon has been also captured by XFEM simulation results (shown in enlarged view of computational result in Fig. 7). A good agreement of simulation with experiment has achieved by XFEM methodology without any mesh refinement and remeshing algorithm. Present work concludes that PAHT significantly improves the mechanical properties of cryorolled alloys. The yield and tensile strength is increased by 12% and 21% respectively. The ductility of ACR alloy is enhanced twice as that of cryorolled alloys. PAHT also enhances the fatigue performance of ACR alloys. Higher fatigue life is obtained for ACR alloys at each of the tested strain amplitudes as compared with CR alloys. FEM coupled with Chaboche kinematic hardening model have shown excellent capability to simulate experimental hysteresis loops. The elasto-plasto simulations performed by XFEM successfully simulated the tensile behavior of CR and ACR conditions of AA 5754 alloy. Bari, S., Hassan, T., 2002. An advancement in cyclic plasticity modeling for multiaxial ratcheting simulation. International Journal of Plasticity 18, 873 – 894. Borrego, L., Abreu, L., Costa, J., Ferreira, J., 2004. Analysis of low cycle fatigue in AlMgSi aluminium alloys. Engineering Failure Analysis 11, 715 – 725. Krishna, K.S.V.B.R., Chandra, S.K, Tejas, R., Naga, K.N., Sivaprasad, K., Narayanasamy, R., 2015. Effect of cryorolling on the mechanical properties of AA5083 alloy and the Portevin-Le Chatelier phenomenon. Materials & Design 67, 107 – 117. Kumar, P., Singh, A., 2017. Investigation of Mechanical Properties and Fracture Simulation of Solution-Treated AA 5754. Journal of Materials Engineering and Performance 26, 4689 – 4706. Kumar, P., Singh, A., 2018. Experimental and numerical investigation of strain rate effect on low cycle fatigue behaviour of AA 5754 alloy. IOP Conference Series: Materials Science and Engineering, 346. Moës, N., Dolbow, J., Belytschko, T., 1999. A finite element method for crack growth without remeshing. International Journal for Numerical Methods in Engineering 46, 131 – 150. Malekjani, S., Hodgson, P.D., Cizek, P., Sabirov, I., Hilditch, T.B., 2011. Cyclic deformation response of UFG 2024 Al alloy. International Journal of Fatigue 33, 700 – 709. Ozturk, F., Pekel, H., Halkaci, H., 2011. The effect of strain-rate sensitivity on formability of AA 5754-O at cold and warm temperatures. Journal of Materials Engineering and Performance 20, 77 – 81. Paul, S., Sivaprasad, S., Dhar, S., Tarafder, M., Tarafder, S., 2010. Simulation of cyclic plastic deformation response in SA333 C-Mn steel by a kinematic hardening model. Computational Materials Science 48, 662 – 671. Panigrahi, S., Jayaganthan, R., 2011. Development of ultrafine grained high strength age hardenable Al 7075 alloy by cryorolling. Materials & Design 32, 3150 – 3160. Singh, D., Rao, P.N.P., Jayaganthan, R., 2013. Effect of deformation temperature on mechanical properties of ultrafine grained Al – Mg alloys processed by rolling. Materials & Design 50, 646 – 655. Vinogradov, A., Hashimoto, S., 2001. Multiscale phenomena in fatigue of ultra-fine grain materials — an overview. Materials Transactions 42, 74 – 84. Yao, X., Zajac, S., Hutchinson, B., 2000. The strain-rate sensitivity of flow stress and work-hardening rate in a hot deformed Al-1.0 Mg alloy. Journal of Materials Science Letters 19, 743 – 744. 5. Conclusions References