AL6061 will meet your needs, if you need aluminum alloy with high strength-to-weight ratio, that offers good machinability and weldability.
But, AL6063 is the best suitable for your project requirements, if your projects need aluminum alloy that is extrudable with great corrosion resistance and excellent surface treatment.
AL6061 is typically used in the applications that require higher strength. 6061 alluminium has a lower melting temperature, lower thermal conductivity, and lower heat capacity.
Compared to AL6063-T6, AL6061-T6 has a higher yield strengthh and fatigue strength, as well as less corrosion resistance.
Compared to AL6061-T6, AL6063 has a higher melting temperature, higher thermal conductivity, and higer heat capacity.
AL6063 has excellent surface treatment than AL6061, which is preferrable for architectural application.
