Preparation of semi-solid 7075 aluminum alloy slurry by serpentine pouring channel
(School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China)
Abstract: The semi-solid slurry of 7075 aluminum alloy was prepared by a serpentine pouring channel (SCP). Influences of pouring temperature and the number of turns on the microstructure of semi-solid 7075 alloy slurry were investigated. The results demonstrated that the semi-solid 7075 aluminum alloy slurry with satisfied quality could be generated by a serpentine pouring channel when the pouring temperature was in the range of 680-700 °C. At a given pouring temperature, the equivalent size of the primary α(Al) grains decreased and the shape factor increased with the increase of the number of turns. During the slurry preparation of semi-solid 7075 aluminum alloy, the flow direction of alloy melt changed many times when it flowed in a curved and closed serpentine channel. With the effect of “stirring” in it , the primary nuclei gradually evolved into spherical and near-spherical grains.
Key words: 7075 aluminum alloy; semi-solid slurry; serpentine channel; primary α(Al)