following conclusions based on the results of the procedure: • Wrought alloys of the 6000 series can be cast into intricate shapes if both the chemistry and casting process are optimized to control the incidence of hot tearing.


• T e iron phases inherent in 6000 series wrought alloy compositions must be controlled via a combina- tion of freezing rate, iron content and thermal dissolution or break- up of the phases during the heat treatment process.


• Alloy 6082 showed a more rapid deterioration in ductility with slower cooling rates than 6061.


• Between the 6061 and 6082 alloys, 6061 was more amenable to microstructural control and high mechanical properties. T e alloy’s microstructure was more amenable to control via heat treatment.


• For 6061, six hours at 1,058F (570C) yielded suffi cient conver- sion of the microstructure. T e 6082 alloy benefi ted from a longer homogenizing treatment of 12 hours.


• Beyond 12 hours, both alloys showed a reduction in toughness.


• Iron levels between 0.1 and 0.15% seemed equally eff ective in 6061. T e 6082 alloy showed a greater tendency towards degradation in properties with an increased iron level.


• Composition and alloy treatment with grain refi ners and strontium can aff ect the tendency towards hot tearing of alloys like 6061.


• Casting process variables also affect the properties achievable in 6061 alloys, with marked differences seen among semi-solid castings, die castings and components cast in the ablation process. 


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