Microstructure and Mechanical Properties of Horizontal Continuous Casting Al-18%Si Alloy Billets
Horizontal continuous casting (HCC) Al-18%Si alloy billets were prepared with the addition of fine-grained Al-18%Si as a master alloy. The influence of cooling conditions and this fine-grained structural materials addition on the microstructure and tensile properties were studied. The uniformity of the HCC Al-18%Si alloy billets was also analyzed. The results denote that the HCC Al-18% Si alloy billets showed finer microstructure and better mechanical properties after double cooling. Fine-grained structural material addition can effectively reduce macrosegregation and make both primary and eutectic silicon much finer. The ultimate tensile strength clearly increased with an addition of 15 percent fine-grained structural material compared to the HCC alloy with no addition of fine-grained structural material. However, a small decrease occurred after an addition of fine-grained structural material up to 30 percent.