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采用挤压铸造工艺制备了高速机车用Al-Zn-Mg-Cu合金传动空心轴,研究了比压和Al-5Ti-1B+Al-10RE双细化剂对挤压铸造Al-Zn-Mg-Cu合金传动空心轴微观组织的影响。结果表明,随着比压的不断增大,挤压铸造Al-Zn-Mg-Cu合金空心轴试样中初生α-Al晶粒的形状不断变得圆整,晶粒尺寸不断变小;当比压达到160MPa时,初生α-Al晶粒中粗大的树枝晶基本消失,试样组织为非枝晶组织,试样的平均晶粒直径为25μm,平均等效圆度为0.73;随着双细化剂中Al-5Ti-1B加入量的减少、Al-10RE加入量的增加,试样的平均晶粒直径显著减小,而试样的平均等效圆度变化不大,基本上在0.65～0.75之间;当添加1%的Al-5Ti-1B+3%的Al-10RE时,试样的平均晶粒直径为21μm,平均等效圆度为0.70。
Al-Zn-Mg-Cu alloy hollow shaft for high speed locomotive was prepared by squeeze casting process. The effect of specific pressure and Al-5Ti-1B + Al- Cu Alloy Driven Hollow Shaft Microstructure. The results show that with the increase of specific pressure, the shape of primary α-Al grains in squeeze-cast hollow-shaft Al-Zn-Mg-Cu alloy becomes round and the grain size decreases. When the specific pressure is up to 160 MPa, the coarse dendrites in the primary α-Al grains disappear and the microstructure of the sample is non-dendritic. The average grain diameter of the sample is 25 μm and the average equivalent circularity is 0.73. The decrease of the amount of Al-5Ti-1B added in the refiner and the increase of the amount of Al-10RE, the average grain diameter of the sample decreased significantly, while the average equivalent circularity of the sample did not change much, basically at 0.65 ~ 0.75. When 1% Al-5Ti-1B + 3% Al-10RE was added, the average crystal grain diameter of the sample was 21μm and the average equivalent circularity was 0.70.