Atmospheric Corrosion Behavior of Aluminum-Zinc Alloy-Coated Steel

The atmospheric corrosion behavior of a hot-rolled strip with four types (I–IV) of oxide scale was investigated using the accelerated wet–dry cycle corrosion test. Corrosion resistance and porosity of oxide scale were studied by potentiometric polarization measurements. Characterization of samples after 80 cycles of the wet–dry corrosion test showed that scale comprised wüstite and magnetite had strongest corrosion resistance. Oxide scale composed of inner magnetite/iron (>70%) and an outer magnetite layer had the weakest corrosion resistance. The corrosion kinetics (weight gain) of each type of oxide scale followed an initial linear and then parabolic (at middle to late corrosion) relationship. This could be predicted by a simple kinetic model which showed good agreement with the experimental results. Analysis of the potentiometric polarization curves, obtained from oxide coated steel electrodes, revealed that the type I oxide scale had the highest porosity, and the corrosion mechanism resulted from the joint effects of electrochemical behavior and the porosity of the oxide scale. In the initial stage of corrosion, the corrosion product nucleated and an outer rust layer formed. As the thickness of outer rust layer increased, the corrosion product developed on the scale defects. An inner rust layer then formed in the localized pits as crack growth of the scale. This attacked the scale and expanded into the substrate during the later stage of corrosion. At this stage, the protective effect of the oxide scale was lost.

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Evaluation Method for Time-Dependent Corrosion Behavior of Carbon Steel Plate Using Atmospheric Corrosion Monitoring Sensor

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.417-418.417 ◽

2009 ◽

Vol 417-418 ◽

pp. 417-420 ◽

Cited By ~ 2

Author(s):

Shigenobu Kainuma ◽

Kunihiro Sugitani ◽

Yoshihiro Ito ◽

In Tae Kim

Keyword(s):

Carbon Steel ◽

Corrosion Behavior ◽

Atmospheric Corrosion ◽

Evaluation Method ◽

Steel Plates ◽

Time Dependent ◽

Corrosion Monitoring ◽

Corrosion Sensor ◽

Atmospheric Exposure ◽

Corrosive Environments

The purpose of this research is to propose a method for evaluating the time-dependent corrosion behavior of carbon steel plates using an atmospheric corrosion monitor (ACM) corrosion sensor consisting of a Fe/Ag-galvanic couple. Atmospheric exposure tests were carried out on steel　plates for periods of 6, 12, and 24-months on the island of Okinawa in Japan. The Specimens were mounted on racks at angles of 0, 45 and 90 to the horizontal to obtain corrosion data in various corrosive environments. In addition, the environments of the skyward- and groundward-facing surfaces of the specimens were monitored using ACM sensors. The sensor outputs were recorded during the exposure tests.

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Atmospheric corrosion behavior of field-exposed magnesium alloys: Influences of chemical composition and microstructure

Corrosion Science ◽

10.1016/j.corsci.2015.08.021 ◽

2015 ◽

Vol 100 ◽

pp. 353-364 ◽

Cited By ~ 24

Author(s):

Jinsun Liao ◽

Makoto Hotta

Keyword(s):

Chemical Composition ◽

Magnesium Alloys ◽

Corrosion Behavior ◽

Atmospheric Corrosion

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