Cold rolling of galvanized strips: A new approach to the evaluation of zinc fines formation

The study concerns a specific cold rolling process called skin-pass with a very low reduction ratio. The skin-pass allows a roughness transfer from the work roll to the galvanized strip. The goal of this paper is to propose a predictive approach to the formation of zinc fines. First, the skin-pass contact conditions were reproduced on a specific testing device, called the Skin-pass Upsetting Rolling Test (SKURT) developed in the authors’ laboratory. Tests on galvanized strips were performed and the zinc fines produced quantified on the strip and on the tool. Secondly, the numerical model was refined at the vicinity of the contact zone taking into account different surface profiles of the roll. Material data were coupled with Lemaitreʹs damage criterion in order to predict the wrenching phenomena of the zinc coating. These predictions were compared with experimental measurements. The correlation was found to be good and a less polluting roll profile is numerically validated.