The commercial alloy of aluminium 6063 belongs to the system Aluminium-Magnesium-Silicon, is characterized
by its high capacity to the extrusion, for what it must expire with requirements in mechanical properties and of
superficial quality, such as low roughness, free of cracks or pits. To assurance a microstructure adapted for the
extrusion a homogenized thermal treatment is applied to the alloy. Nevertheless, there has not been sufficiently
studied the effect of the thermal treatment in the resistance to the corrosion. In this research was evaluated the
effect of temperature and time of maintenance the heat treatment of homogenized on the resistance to the
corrosion, and microstructure of the alloy 6063. The assessment of the properties of the alloy took place before
and after treatment. The times of homogenized were 1,2 y 3 hours at temperatures of homogenization of 560, 580
y 600 °C. The corrosion resistance was evaluated by electrochemical technique of potentiodinamic cyclic
polarization (ASTM G-69). The microstructural characterization of alloy and corrosion products was assessed by
optical microscopy techniques with image analysis, scanning electron microscopy with microanalysis by EDS.
The results show that increasing the time homogenized influences resistance to corrosion, in the grain size and the
volume fraction transformed of β-AlFeSi (Al 5 FeSi) phase to α-AlFeSi (Al 8 Fe 2 Si), obtaining the best properties
for a time of 3 hours. The mechanism of corrosive attack occurs by the formation of local chemical cell, caused by
differences in the electrochemical activity between precipitated phases and matrix alloy heat-treated.
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