中文摘要：

对采用近液相线半连续铸造技术制备的AlSi7MgBe合金坯料进行半固态挤压成形，通过组织与性能的分析，研究了AlSi7MgBe合金的半固态挤压成形性．结果表明：用近液相线半连续铸造技术制备的AlSi7MgBe合金坯料具有均匀、细小的蔷薇状组织，在575℃对其二次加热可获得稳定的、适合于半固态触变成形的球化组织，进行半固态挤压成形可获得表面光洁，组织细小、分布均匀的成形件，在540℃固溶5h然后175℃时效10h处理，其抗拉强度为325MPa，伸长率为14．6％，表明具有良好的半固态挤压成形性．

英文摘要：

The semi-solid thixo-extruding feasibility of AlSiTMgBe alloy cast by near-liquidus semi-continuous casting （NLSC） process was studied by analyzing the microstructures and properties of extruded bars. The results shown that the microstructure of AlSi/MgBe alloy billets cast by NLSC consists mainly of the homogeneous, fine rosette-shaped grains. The microstructures of the billets, reheated and held at 575℃, are stable and near-spherical grains which are suitable for semi-solid thixoforming. The semi-solid thixoextruded bars of the AlSi7MgBe alloy billet are facial-smoothed, microstructure-fined and homogeneous. Treated by the solution at 540℃ for 5 hours and aging at 115℃ for 10 hours, the tensile strength of the semi-solid extruded bars is above 325 MPa and the elongation rate is above 14.5%.