Method for preparing hypo-eutectic aluminium-silicon alloy material

The invention discloses a method for preparing a hypo-eutectic aluminium-silicon alloy material. A preparing technology of combining multiplex microalloy compound modification and semi-solid-state extrusion is adopted. Firstly, multiplex modification is adopted for modification and refining of eutectic Si and refining of eutectic colonies; then under a semi-solid-state technology, alpha-Al dentritic crystals are crushed and balled, and meanwhile, eutectic Si is further refined and uniformly distributed on a base body. The alloy structure is refined, the alloy compactness is improved, thus thestrength, tenacity, electric conductivity and thermal conductivity of the alloy are greatly increased, and the prepared semi-solid-state multiplex microalloy hypo-eutectic aluminium-silicon alloy hasthe tensile strength at the room temperature of 330-480 Mpa, the yield strength of 280-420 Mpa, the ductility of 7-14%, the electricity conducting rate of 43.7-59.2% IACS and the heat conducting rateof 168.2-198.8 W.m.K