مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

Aluminum anodes have been widely used in the cathodic protection of marine structures. However there are conditions in which these anodes become passivated or face some localized or unwanted corrosion, which influences their efficiency. Addition of alloying elements such as Zn and In not only have improved the efficiency ofthe anodes but also the effect ofcasting parameters such as ultra melt temperature Tm , mold temperature and grain refiners can adversely influence the capacity of aluminum anodes. In this work the effects of ultra melt temperature and mold temperature have been studied on the potential and current capacity of Al-Zn-In anodes. Electrochemical polarization and NACE standard methods were used to evaluate the anodic behavior, potential and current capacity of the anodes. It is shown that metallic molds having higher temperatures could provide better condition for obtaining homogenous structures with minor inclusions. The optimum condition of anode operation may be provided where mold and pouring temperatures equal to 400°C and 710°C respectively, in which a fine structure, phase distribution and lack ofcasting faults are obtained. The microstructures that can provide a homogenous anodic dissolution bring by itselfoptimum efficiency ofthe anodes.