The aluminium-silicon alloys are widely used
in the automotive industry, due to their excellent castability, good corrosion
resistance and mechanical properties, which can be further improved by eutectic
Si modification with Sr, Na or Sb as modifying elements and the precipitation
of nanometric Mg2Si precipitates during T6 heat treatment.
Recently, the use of secondary alloys has
attracted considerable interest, as these alloys offer several advantages over
conventional primary alloys, such as cheaper raw material, less energy consumption during
their manufacturing and protection of resources.
However, these types of alloys usually contain
high levels of
alloying elements and/or impurities such as Fe, Cu and Zn which may affect
adversely the microstructure, mechanical properties and corrosion resistance.
The effect of these compounds on the corrosion
behaviour was studied.