Basak, Shamik; Katiyar, Bhupesh Singh; Orozco Gonzalez, Pilar; Baltazar Hernández, Víctor Hugo; Arora, Kanwer Singh; Panda, Sushanta Kumar
Resumen:
In the present study, tailor-welded blanks (TWBs) of dissimilar material combination were fabricated by laser welding of
interstitial-free (IF) and dual-phase (DP) steels using 2.4-kW power and 4 m/min scan speed. Subsequently, TWBs of asreceived
sheet materials and IF steels were pre-strained up to 20% major strain in the deformed specimens through an equibiaxial
pre-straining setup. It was found that highly non-uniform strain distribution with nearly plane strain deformation mode
was induced in the pre-strained TWBs, whereas an equi-biaxial strain was recorded for IF monolithic blank. Microhardness
profiles and the effect of weld zone on the microstructural and mechanical properties of the as-received and pre-strained TWBs
were studied. Further, the forming limit diagrams (ε-FLDs) of as-received TWB and IF steel were experimentally evaluated. The
ε-FLD of pre-strained TWBs was experimentally determined, and ε-FLD of the pre-strained IF material was estimated using the
Yld89 anisotropy plasticity model with the Hollomon hardening law. Subsequently, all these respective ε-FLDs were implemented
as damage models in the FE simulations for predicting the limiting dome height (LDH) of as-received and pre-strained
TWBs. It was observed that the error in LDH prediction of pre-strainedTWB domes was within 9.1% when the estimated ε-FLD
of the pre-strained IF material was used as a damage model. The FE-predicted strain distributions and weld line movements of
TWBs after the second stage of deformation were also successfully validated with the experimental data.