Influence of Si and Mg Contents on the Mechanical Behavior of Al-Mg-Si Alloys in the Semi-Solid State under Isothermal and Non-Isothermal Conditions
The shear behavior of aluminum alloys containing increased amounts of Si or Mg compared with the 6061 alloy has been investigated by carrying out isothermal and non-isothermal tests in the mushy state during solidification. In isothermal conditions, it is shown that (i) an increase in Mg content leads to a more resistant semi-solid alloy compared with the 6061 alloy for the same solid fraction and (ii) an increase in Si content leads to a more brittle mushy alloy. In non-isothermal conditions, stress increases continuously with decreasing temperature with the formation of cracks for some compositions. This study shows that an increase in Mg content seems to be the most appropriate solution to reduce the formation of cracks in a solidifying 6061 alloy.
Hajo Dieringa, Norbert Hort and Karl Ulrich Kainer
E. Giraud et al., "Influence of Si and Mg Contents on the Mechanical Behavior of Al-Mg-Si Alloys in the Semi-Solid State under Isothermal and Non-Isothermal Conditions", Materials Science Forum, Vol. 690, pp. 73-76, 2011