液相线铸造Al-18Si合金的凝固组织与力学性能研究OACSTPCD

The solidification microstructure and mechanical properties of liquidus cast Al-18Si alloy were studied using optical microscopy,Image-Pro Plus software,X-ray diffractometer,and universal tensile testing machine.The results indicated that with the increase of holding time at liquidus temperature,the size of primary silicon in Al-18Si hypereutectic aluminum silicon alloy showed a trend of first decreasing and then increasing,while the mechanical properties showed a trend of first increasing and then decreasing.Compared with ordinary casting,the liquidus casting reduced the average size of the primary silicon in the Al-18Si alloy by 30.6%,and increased the tensile strength and elongation of the alloy by 27%and 108%,respectively.Therefore,the liquidus casting was an effective method to improve the solidification microstructure and mechanical properties of hypereutectic aluminum silicon alloys.