The dual effect of stem extract of Brahmi(Bacopamonnieri) and Henna as a green corrosion inhibitor for low carbon steel in 0.5 M NaOH solution

The effect of stem Extract of Brahmi (Bacopamonnieri) and Henna on the rate of corrosion of low carbon steel were investigated in a solution of 0.5 M NaOH using the methods of weight loss measurements and potentiodynamic polarization. The findings revealed that the dual effect of stem extract had the role of being an effective inhibitor, the loss of weight experiments and the inhibition efficiencies gained from the polarization process were well matched. It was proved by conducting the potentiodynamic polarization method that the stem extract is an inhibitor of mixed type in an alkaline solution of 0.5 NaOH for low carbon steel through avoiding the reactions of both cathodic and anodic on a metal surface. Thus, the findings gained from the experiment of weight loss reveals the same effect of corrosion’s inhibitions, the results show that when using different concentration of extract of Brahimi (Bacopamonnieri) and Henna solutions ranging between (0.5–2)% in 0.5 M NaOH at room temperature and 1 atm, the efficiency IEp % increased up to 80% which is resulting from polarization while the efficiency IE% increased up to 65% which is resulting from weight loss method.