Comparative surface-texture sustainability of plain and corrugated high-strength high carbon steel bar in different chloride ion concentrations from near neutral to alkaline pH from electrochemical aspects

Abstract High-strength high carbon steel bar has been adopted for maintaining the sustainability of complex construction in recent years. This work aimed to investigate the corrosion resistance of two different surface textures (plain and corrugated) of the same high-strength high carbon (HSHC) steel bars in different pH electrolytes with different Cl − concentrations at the preliminary stage from the electrochemical approach. In-house tensile test revealed that the plain displayed a necking fracture and had an elongation 21.74% longer than the corrugated which showed a peel-off fracture. The plain and the corrugated had similar corrosion potentials after 8-h immersion, which were between − 600 and − 700 mV at pH 8.2, between − 350 and − 500 mV at pH 12.3 and between − 300 and − 400 mV at pH 13.4. The corrosion current was between 10 and 12 µA/cm 2 for both HSHC steel bars in 0.5 M Cl − at pH 12.3 and 8.2; while at pH 13.4 the plain was 1.80 µA/cm 2 and the corrugated was 0.49 µA/cm 2 . Only the plain showed the passivation and pitting potential in 0.1 and 0.25 M Cl − at pH 12.3. Electrochemical impedance spectroscopy revealed that the corrugated had the passive film and charge transfer resistance better than the plain at pH 13.4. On the other hand, Mott-Schottky analysis also exhibited that the corrugated in 0.1 M Cl − at pH 13.4 had a space charge layer thicker than the plain.