离心真空吸铸对铝合金凝固组织与性能的影响

摘要

离心真空吸铸在小型复杂薄壁构件液态成形方面具有技术优势.为探究其工艺参数对组织与性能的影响开展了试验研究.结果表明,真空吸铸开始时施加离心旋转,可提高金属液的充型能力,但也会在铸件中形成铸造缺陷,降低铸件力学性能;真空吸铸充型完成后对铸型施加离心旋转,不仅可以提高凝固补缩能力,而且会起到机械震荡与破碎晶粒作用,使晶粒得到细化并且均匀性好,提高铸件力学性能;此外合理确定施加离心旋转和卸除真空时间节点,不仅可以提高铸件力学性能,还可以有效提高金属的利用率.%Centrifugal vacuum suction casting has technical advantages in small complex thin-walled components.In this paper,the experimental search was carried out to study the effect of centrifugal vacuum suction casting process parameters on microstructure and properties. The results show that application of centrifugal rotation at the beginning of vacuum suction casting can increase the filling ability of molten metal, but also form casting defects in the casting to degrade the mechanical properties of the casting.After the mold cauity was filled with metal using vacuum suction casting,the application of centrifugal rotation not only can improve the solidification feeding capacity,but also play the role in mechanical shock and broken grains,so that the grain refines and has good uniformity,and the mechanical properties of the casting are improved.In addition, it is reasonable to determine that the application of centrifugal rotation and unloading vacuum time node,which not only can improve the mechanical properties of the casting,but also can improve the utilization of metals effectively.