The Analysis of Electroplating Methods on Corrosion Resistance
Steel is used for infrastructure, appliances, buildings, and other materials due to its tough, weldable, and durable nature; however, it is susceptible to corrosion. Zinc, on the other hand, has high corrosion resistance, though it lacks many desirable properties that steel has. By electroplating steel with zinc, chemically producing a layer of zinc around steel, the resulting material can retain the positive qualities of steel while having an additional layer of corrosion protection. The objective of this experiment was to determine which combination of factors for electroplating steel would yield the highest corrosion protection when exposed to saltwater. The experimental design was based off of a two-factor Design of Experiment (DOE), and it was analyzed with that DOE, along with an ANOVA test. Two critical factors in the electroplating process were examined: potential difference and the duration the steel was electroplated. Each steel sample was electroplated with zinc under a specific set of conditions according to the DOE. After the steel samples were plated, they were immersed in salt water for calculation of the response variable: the change in mass per unit area from before corrosion testing to after. A partnership with DENSO allowed for surface examination of the samples before plating, after plating, and after corrosion testing with a Scanning Electron Microscope (SEM). After experimentation, observation, and statistical analyzation, it was determined that both potential difference and time were significant, while the interaction effect was not. The ANOVA test further validated the effectiveness of the variables with a rejection of the null hypothesis - that all populations were the same. It was proven that although increasing voltage and time does increase the mass and thickness of the plated layer, the quality declines. A direct relationship does not exist between the quantity and quality of an electroplated layer.
Research Conducted By:
Johana Lund
Fraser High School
Owen Pierce
Cousino High School
Warren Consolidated Schools