EFEITO DE REVESTIMENTOS GALVANIZADOS POR IMERSÃO A QUENTE NO COEFICIENTE DE ATRITO DE UM AÇO BIFÁSICO DESTINADO À INDÚSTRIA AUTOMOTIVA

The need for weight reduction in the automotive industry, developing better design and improve corrosion resistance of the automotive vehicles has forced the steel industry to produce high-strength galvanized steel. However, when subjected to stamping process can suffer wear of the galvanizing surface, powdering and reduced corrosion resistance. The study evaluated the effect of coatings with Zn-Pure (GI) and Zn-Fe (GA) in the coefficient of friction of biphasic steel (DP600) using flat tribometer and characterization process of the coating by optical microscopy, scanning electron microscopy and energy dispersive spectroscopy. As a result, the coatings studied influence directly the behavior of the friction of stamping. For DPGI, is observed lower coefficient of friction if compared to DPGA, due of his microstructure composed of zinc pure (η phase). This microstructure can increase the susceptibility to abrasion phenomenon called stick slip. Despite the observed differences, there are favorable conditions for use of both materials in stamping processes and painting