Study of hardening models in automotive steels using the finite element method and the backscattered electron diffraction technique

Erika Aparecida da Silva, José Wilson de Jesus Silva, Nilo Antonio de Souza Sampaio, Jean Pierre Faye, Joel Alexis, Antonio Jorge Abdalla

Abstract


In this work, the objective was to correlate anisotropy with the mechanical and microstructural behavior of two high strength steels used in vehicle production in order to obtain variables to alter future manufacturing processes in order to obtain steels with a lower elastic return, known as springback effect, which means geometric changes suffered by the part at the end of the plastic deformation process, after the release of the forces applied by the stamping tool and this causes dimensional failures that compromise the production. In this research, biphasic steel and one low carbon steel were evaluated, being Docol_DL800 and LC200 their trade names, respectively. Tensile tests and three-point bending in air were performed to determine the mechanical properties and behaviors and these results were compared with those obtained by computational simulation using the finite element method and were also correlated with microstructural data from the backscattered electron technique. The results indicate that biphasic steel has a higher hardening allowing a greater springback effect due to its microstructure with ferrite and martensite, high grain refinement, greater amount of elastic residual energy and a lower degree of disorientation after mechanical conformation, creating the effect Bauschinger. Already the steel LC200 presented a smaller degree of springback thanks to the more isotropic hardening due to the increase in the degree of grain disorientation after the conformation. Thus, it was concluded that the manufacturing processes of these steels should seek to combine high mechanical strength with a more isotropic behavior.


Keywords


springback; AHSS; sheet metal forming; finite element analysis, high strength steels, EBSD

References


Chongthairungruang B., Uthaisangsuk V., Suranuntchai S., Jirathearanat S. (2013), “Springback prediction in sheet metal forming of high strength steels” Materials and Design v. 50, p. 253-266.

Gan W., Babu S. S., Kapustka N., Wagoner, R. H. (2006), “Microstructural Effects on the Springback of Advanced High Strength Steel”, Metallurgical and Materials Transactions A, Columbus, v.37A, p.3221-3231.

Ghaei A., Green D. E.; Aryanpour A. (2015), “Springback simulation of advanced high strength steels considering nonlinear elastic unloading-reloading behavior” Materials and Design v. 88, p. 461-470.

Gorni A. A. (2011), “A metalurgia por trás dos aços avançados de alta resistência”, Industrial Heating. Julho a Setembro.

Hassan H. U., Traphöner A. G., Tekkaya A. (2016), “Accurate springback prediction in deep drawing using pre-strain based multiple cyclic stress–strain curves in finite element simulation” International Journal of Mechanical Sciences v. 110, p. 229-241, 2016.

Li H., Chen J., Yang J. (2012), “Experimental and numerical investigation of laminated steel sheet in V-bending process considering nonlinear visco-elasticity of polymer layer” Journal of Materials Processing Technology 212, p. 36-45.

Ma Z., Tong G. Q., Chen F., Wang Q., Wang S. (2015), “Grain size effect on springback behavior in bending of Ti-2.5Al-1.5Mn foils” Journal of Materials Processing Technology 224, p. 11-17.

Numisheet 2002. (2002), “Proceedings of the 5th International Conference on Numerical Simulations of 3-D sheet Metal Forming Processes”, D-Y. Yang et al. (eds.), Jeju Island, Korea. Available in: < www.numsiheet2002.org>.

Oxford Instruments HKL. (2007), “Manual EBSD, 2007”, Available in: .

Placidi F.; Vadori R.; Cimolin F.; Campana F. (2008), “An efficient approach to springback compensation for ultra high strength steel structural components for the automotive field” New Developments.

Qudeiri, J.A., Khadra, F.A., Al-Ahmari, A., Umar, U. (2013), “Effect of Material and Geometrical Parameters on the Springback of Metallic Sheets”, Life Science Journal, v.10(2), p.1531-1537.

Silva E. A., “Estudo da correlação entre os modelos de encruamento e as características cristalográficas em aços avançados de alta resistência submetidos ao efeito springback”, Tese de doutorado - Unesp. 206p. 2016.

Silva E. A., Pereira, M. S., Faye J. P., Ribeiro R. B., Sampaio N. A. S., Silva J. W. J, “Identification of elastic-plastic behavior in AHSS using the isotropic hardening model by the finite element method and EBSD”, International Journal of Advanced Engineerging Research and Science (IJAERS), v.6, issue 5, p. 649-658, May 2019.

Sun L., Wagoner R. H. (2011), “Complex unloading behavior: nature of the deformation and its consistent constitutive representation” Int. J. Plast. v. 27, p. 1126–1144.

Uemori T., Yoshida F. (2002), “A model of large-strain cyclic plasticity describing the bauschinger effect and work hardening stagnation”, Int J Plast, 18:661–86.

Yamano T., Iwaya J. (2005), “Study of counter measure of side wall curl usingoverrun-inducing punch”, J of the Japan Society for Technology of Plasticity. Vol. 46, Issue 534, Pages 630-635.

Yang X., Choi C., Sever N. K., Altan T. (2016), “Prediction of springback in air-bending of Advanced High Strength Steel (DP780) considering Young’s modulus variation and with a piecewise hardening function” International Journal of Mechanical Sciences 105, p. 266-272.




DOI: http://dx.doi.org/10.33448/rsd-v9i1.1535

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