Electrochemical corrosion behavior of Al7075 rotating disc electrode in neutral solution containing l-glutamine as a green inhibitor

This is a study of the electrochemical corrosion behavior of aluminum alloy Al7075 and its corrosion inhibition using l-glutamine in 3.5% NaCl solution under different hydrodynamic conditions. The hydrodynamic conditions were simulated by using a rotating disc electrode. The results showed that an increase in rotation speed leads to a higher corrosion current density, while the charge transfer resistance decreases and corrosion potential shifts toward more positive values. The inhibition efficiency depends on rotation speed. That is, the efficiency was low in stagnant solution, but enhanced significantly under hydrodynamic conditions. The phenomenon was attributed to the increased mass transport of inhibitor's molecules to the electrode surface that is advantageous for improvement of inhibition efficiency. However, higher rotation speeds (Omega a parts per thousand yen 1,500 rpm) cause a slight reduction of efficiency due to higher shear stresses.