Abstract
Two interstitial-free (IF), titanium added steels and one low carbon Al killed steel were subjected to the 0 deg bend test and to the low temperature impact loading and fracturing with aim to describe the deformation behavior and the failure modes of the steel-zinc coating interface. The system of steel sheet-intermetallic phases layer-pure zinc phase after the deformation was studied from both compression and strain sides of the sheet materials. It was shown that the failure has been initiated in the intermetallic phases region, meanwhile the uppermost pure zinc phase exhibited very high deformation potential. After the impact load at low temperatures, both IF steels with different zinc coating thicknesses fractured by intergranular decohesion mechanisms, while the low carbon steel exhibited transgranular fracture. The fracturing mechanism of basic steel material remarkably influenced the steel-zinc layer interface failure mode. The zinc layer in all cases fractured by complicated brittle mechanisms.

Key words
hot dip galvanizing, intermetallic phases, deformation, bend testing, compression, strain, low temperature fracture

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