The purpose of this paper is to investigate the inhibition effect of some Chalcone derivatives on the
corrosion behavior of aluminum in 1 M phosphoric acid solutions with and without Chalcone
derivatives and to investigate the influence of halide additives namely: KCl, KBr and KI on the inhibition
efficiency of aluminum. For this purpose, polarization (DC) and weight loss measurements were used.
To increase the inhibition efficiency, halide anions were added to the corrosive medium. The effect of
temperature also was studied over the range 30 to 50°C. Thermodynamic parameters (ΔH*, ΔS*) were
calculated and discussed. The results indicated that the corrosion of aluminum was affected by the
addition of Chalcone derivatives in 1 M H3PO4. The efficiency of Chalcone derivatives increases with the
increase in the derivatives concentration but decreases with a rise in temperature. The effect of addition
of halide ions to the corrosive solution increases the inhibition efficiency by more than 30%. These
compounds were adsorbed on aluminum surface obeying Freundlich adsorption isotherm and they
behave as mixed type inhibitors. The main objectives of this study were to gain some insight into the
protection of aluminum in 1 M H3PO4 medium using some Chalcone derivatives.