INFLUENCE OF A COOLING LIQUID ON THE CORROSION BEHAVIOUR OF AlMn ALLOY

Abstract

International audienceElectrochemical behaviour of AlMn alloys was determined by stationary electrochemical methods: potential versus time, polarization curves and linear polarization resistance recorded at different temperatures in a commercial cooling liquid, Glaceol D, which contains tolyltriazole as a corrosion inhibitor. The later was found to be an anodic corrosion inhibitor. The inhibition efficiency increases as the added concentration of the cooling liquid is increased (95% for 50%vol. Glaceol D). At the ambient temperature, the corrosion resistance of this aluminium alloy is increased with the immersion time, unfortunately at higher temperatures the corrosion rate is increased too. The intermetallic particles, such as Al-6(MnFe) and alpha-Al(Mn,Fe)Si, were found to be the cathodic sites for the corrosion of aluminium matrix