Abstract
Zinc as a metallic coating is a common strategy to protect the carbon steel against corrosion. The most common process of zinc deposition is known as electroplating. Because of the high toxicity of cyanide-based baths, the interest in acid baths has grown, but they present many challenges to be overcome. Several operational parameters and bath constitution – such as current density, pH, and zinc concentration – can impact the current efficiency, deposit quality, and coating morphology. In this work, the process efficiency and the coating morphology were evaluated on electroplated AISI 1008 carbon steel samples. The current density and temperature were individually varied on a range from 7.5 mA.cm-2 to 30.5 mA.cm-2, and from 40 °C to 60 °C, respectively. The process efficiency was evaluated by current efficiency (eC). The surface morphology was analyzed by both optical microscopy (OM) and scanning electron microscopy (SEM). Varying the bath temperature did not promote impacts in the current efficiency, which remained in all temperatures evaluated over 95%. On the other hand, increasing the current density, increased the current efficiency, starting from (85 ± 2)% at 7.5 mA.cm-2 to (92 ± 2)% at 19.0 mA.cm-2, and (95 ± 1)% at 30.5 mA.cm-2. Through OM and SEM analysis, the increase in the temperature tended to turn the coating rougher, and the sample was not completely covered at 7.5 mA.cm-2. Therefore, we recommend the use of a temperature between 40 °C and 50 °C associated with a current density of 30.5 mA.cm-2.
Highlights
Carbon steel is one of the most versatile material due to its good mechanical properties, but they are susceptible to corrosion deterioration [1, 2]
The process efficiency was evaluated by the current efficiency and the surface morphology was performed by optical microscopy (OM)
While the surface morphology characterization was analyzed by images obtained both by optical microscopy (OM, S9, Leica) and by scanning electron microscopy (SEM, VEGA3, Tescan)
Summary
Carbon steel is one of the most versatile material due to its good mechanical properties, but they are susceptible to corrosion deterioration [1, 2]. The corrosion phenomena are a natural and spontaneous process in which the metal returns to its most stable oxidation state [3] These oxidative reactions can compromise the structural integrity and cause severe damages impacting the economy, environmental, and socio-cultural sectors [4,5,6]. In this scenario, the use of zinc as a metallic coating is a common strategy to avoid the corrosion deterioration of carbon steel materials [7]. Zinc electroplating consists of the zinc reduction reaction on the cathode surface This technique is classified as a non-spontaneous process and the use of an external power supply is needed [3]. The process efficiency was evaluated by the current efficiency and the surface morphology was performed by optical microscopy (OM)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
