Issue 61

L. Arfaoui et alii, Frattura ed Integrità Strutturale, 61 (2022) 282-293; DOI: 10.3221/IGF-ESIS.61.19

Identification of the anisotropic behavior of the laser welded Interstitial Free steels subjected to off-axis tensile tests

Arfaoui Latifa University of Tunis El Manar, ENIT, LR-MAI-ENIT, Tunisia arfaoui_latifa@hotmail.fr, https://orcid.org/0000-0001-5019-7479 Samet Amel, Znaidi Amna University of Tunis El Manar, IPEIEM, LR-MAI-ENIT, Tunisia amel.samet@ipeiem.utm.tn, amna.znaidi@ipeiem.utm.tn

A BSTRACT . The main purpose of this paper is to study the anisotropic behavior of laser welded interstitial free steel HC 260Y when it is subjected to monotonic tensile tests. The specimens were cut in different orientations according to the rolling direction, annealed and finally assembled by laser welding. The plastic behavior was modelled using an identification strategy based on a behavior law taking into account the anisotropy of this material, a hardening law describing the evolution of the hardening curves and an evolution law. The proposed identification strategy allowed for a good validation of the model. The model was afterwards used to predict the behavior of the welded material when it is subjected to various solicitations. Finally, the fracture surfaces of the specimens were examined using the scanning electron microscope (SEM) to determine the failure characteristics under the tensile loading. K EYWORDS . Interstitial Free steel; Laser welding; Off-axis tensile tests; anisotropy; Identification strategy; SEM.

Citation: Arfaoui, L., Samet, A., Znaidi, A., Identification of the anisotropic behavior of the laser welded Interstitial Free steels subjected to off-axis tensile tests, Frattura ed Integrità Strutturale, 61 (2022) 282-293.

Received: 18.03.2022 Accepted: 29.05.2022 Online first: 02.06.2022 Published: 01.07.2022

Copyright: © 2022 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

I NTRODUCTION

ith the advent of new generation automobiles, the demand of high formability steels especially Interstitial Free (IF) steels, has progressively accentuated. IF steels are mainly used in autobody fabrication. They are generally formed into intricate shapes at high production rates and manufactured by welding. The excellent formability of IF steels is achieved through the reduction of the amount of interstitial elements, carbon and nitrogen, to an extremely low level [1-3], mainly by the addition of stabilizing elements, such as Titanium and/or Niobium [4-6]. IF steels are cold-rolled into sheets first, in order to fabricate a variety of final product components. However, the cold rolling leads to a directional microstructural texture, and thus anisotropic mechanical properties in the processed steels [7]. W

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