根据铝合金变速箱箱体结构特点,进行了箱体的双重挤压铸造工艺设计。使用Pro CAST有限元模拟软件对铸造工艺参数进行正交试验,确定了最佳的工艺参数;通过单一变量法,确定最佳的局部加压延时参数。结果表明:在浇注温度680℃、压射比压120 MPa、模具温度200℃、局部压力135 MPa、局部加压延时27 s参数下,得到的铸件组织致密,无缩松缩孔缺陷。 According to the structure of aluminum alloy gear box structure, the box has been double extrusion casting process design. Pro CAST finite element simulation software was used to carry out orthogonal test of casting process parameters to determine the best process parameters; by single variable method, to determine the best local pressure delay parameters. The results show that the castings are compact and have no shrinkage shrinkage defects under the conditions of pouring temperature of 680 ℃, injection pressure of 120 MPa, mold temperature of 200 ℃, partial pressure of 135 MPa and local pressure delay of 27 s.