Study through Potentiodynamic Techniques of the Corrosion Resistance of Different Aluminium Base MMC´s with Boron Additions

Abstract

This paper compares wrought aluminium with PM aluminum and PM aluminium alloys with boron-base additions, containing boron carbide and Fe/B (obtained by mechanical alloying during 36 hours from a Fe-B 50% mixture by weight). The effect of sintering temperature for the Fe/B containing material and the effect of mechanical alloying for the boron carbide containing aluminium alloy on the corrosion resistance of those materials have been studied. Their behavior is followed through cyclic anodic polarization curves in chloride media. In the Al+20%Fe/B composite, low sintering temperatures (650-950°C) exert a negative effect. However, when the material was sintered at high temperature (1000-1100°C) its behaviour was very similar to the PM pure aluminium. The effect of mechanical alloying studied in aluminium with boron carbide was also important in corrosion resistance, finding a lower corrosion rate in the mechanically alloyed material.