INVESTIGADORES
ELSNER Cecilia Ines
artículos
Título:
Relationship between texture and corrosion resistance in hot-dip galvanized steel sheets
Autor/es:
P.R. SERÉ; J.D. CULCASI; C.I. ELSNER; A.R. DI SARLI
Revista:
SURFACE AND COATINGS TECHNOLOGY
Editorial:
ELSEVIER SCIENCE SA
Referencias:
Lugar: Amsterdam; Año: 1999 vol. 122 p. 143 - 149
ISSN:
0257-8972
Resumen:
The addition
of lead or antimony to the zinc bath promotes both excessive growth of the zinc
crystals and a dendritic solidification in the form of spangles. This
phenomenon affects not only the zinc coating texture but also its surface
appearance and corrosion resistance. Therefore, the effects on the zinc bath
chemical composition (changed by the addition of lead or antimony) on the
texture and corrosion behaviour of hot-dip galvanized steel sheets were
evaluated. Standardized salt spray tests as well as exposure to a 0.5M NaClO4
solution test were employed. The surface texture was analyzed using X-ray
diffraction (XRD). In order to study the corrosion performance, electrochemical
impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques
were employed. From the experimental results it was concluded that the
characteristic texture of zinc coatings was not modified by an increase in the
antimony content, but an increment in the lead content produced a
crystallographic preferential orientation with the pyramidal family planes
parallel to the coating surface. This last effect deteriorates not only the
surface appearance but also the corrosion resistance of the galvanized steel
sheet.