The effect of hot extrusion conditions on nanostructure and corrosion properties of anodized AA6063 alloy

Samples of AA6063 alloy were extruded at different extrusion temperatures and velocities and anodized using sulfuric acid. Salt spray test was used to measure the resistance of the coating against corrosion. Results demonstrated the formation of a network of beehive cell nanostructure on the surface of all samples. Samples extruded at higher velocity and lower temperature indicated finer recrystallized grain structure and finer beehive cell nanostructure and higher corrosion resistance. In these samples, the surface fraction of the nanocavities was smaller and a smaller fraction of the surface was left unprotected which caused higher corrosion resistant.

Keywords:

AA6063 , hot extrusion , Anodizing , Nanostructure , Corrosion properties