Thin Strip vs Direct Chill Casting: The Effects of Casting Cooling Rate on the As-cast Microstructure of AA6005 Al-Si-Mg Alloy

Aluminum AA6005 sheet produced by Thin Strip (TS) casting was compared to the slabs produced by Direct Chill casting in the as-cast state. Higher cooling rates experienced before, during, and after the solidification for the TS cast sheet showed a finer grain size, smaller secondary dendritic arm spacing, improved solute supersaturation, and a lack of Mg2Si constituents at the grain boundary. These findings showed the effects of cooling rate in the casting process on the as-cast microstructure and provided a basis for further heat-treatment optimization of the TS cast sheet. (C) The Minerals, Metals & Materials Society and ASM International 2022

Automated summary

This study compared the properties of aluminum AA6005 sheet produced by Thin Strip (TS) casting with slabs produced by Direct Chill casting in the as-cast state. The TS cast sheet showed finer grain size, smaller secondary dendritic arm spacing, improved solute supersaturation, and a lack of Mg2Si constituents at the grain boundary due to higher cooling rates. These findings provide a basis for further heat-treatment optimization of TS cast sheet.