Two types of honeys, Trigona sp. and Apis sp. were studied as corrosion inhibitors of aluminium alloy in 1M  H₃PO₄ was investigated by means of weight loss method, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurement. The higher inhibition was measured at optimum concentration 1500 ppm for both honeys. The percentage inhibition efficiency of Trigona sp. obtained from potentiodynamic polarization measurement and impedance were in good correlation which the best inhibition is around 78 - 84%.  Potentiodynamic polarization measurement indicated that the inhibitors act as mixed type inhibitors with predominant anodic inhibition. The adsorption isotherm study revealed that the inhibitor follows Langmuir adsorption model. 

Aluminium alloy;

Corrosion inhibitor;

EIS