51 NACE INTERNATIONAL: VOL. 56, NO. 11 MATERIALS PERFORMANCE NOVEMBER 2017
Continued f rom page 49
incremental rust formation, which indi-
cated zinc corrosion activity and some level
of beneficial cathodic polarization. Even
though rust was observed at defect sites,
the authors note that the extent of corro-
sion probably would have been greater if
zinc pigment was not present in the primer
matrix near the defect sites.
ey conclude that the benefits of
including nanoparticles in zinc-rich primer
coated steel could not be easily ascertained
in the chloride solution immersion tests;
however, they suggest that some level of
enhanced conductivity was present in the
NPE-ZRP coated samples since steel corro-
sion was generally limited at the defect sites
even though anodic currents were high and
consumption of zinc pigments adjacent to
the defects was evident. e authors sug-
gest further testing to determine the role of
the nanoparticles in the polarization behav-
ior of the steel, and to assess the influence
of nanoparticles on the galvanic coupling of
dispersed zinc pigments and the long-term
durability of NPE-ZRP.