Corrosion Mechanisms of Screw Spikes
Screw Spikes, made of Q235 carbon structural steel with trace elements like C, Mn, Si, S, and P, undergo a complicated process of oxidation and corrosion in the atmosphere.
Different corrosion mechanisms include:
Chemical Corrosion: Primarily gas corrosion, involving the oxidation process of metal with oxygen. The formation of an oxide film on the metal surface controls the rate of oxidation. Reaction: 3Fe + 2O2 → Fe3O4
Electrochemical Corrosion: After connecting to the concrete pillow, a water film forms, creating a micro battery on the metal surface. The presence of an electrolyte film facilitates electrochemical corrosion, with CO2, SO2, NO2 dissolving in the water film to form a weak acid electrolyte solution.
Reaction: 2Fe + O2 + 2H2O → 2Fe(OH)2, then 4Fe(OH)2 + O2 + 2H2O → 4Fe(OH)3 In summary, the corrosion of screw spikes is mainly attributed to oxygen-absorbing corrosion, influenced by various environmental pollutants and factors.