Numerical Simulation And Process Optimization Of Low Pressure Casting Aluminum Alloy Large Complicated Case

The low pressure casting is a kind of anti gravity casting, the liquid alloy is filled with the mold cavity under the pressure acting along the liquid alloy, and the casting method is solidified under some pressure. It is a more advanced casting forming method. Casting numerical simulation technology can simulate the solidification process of low-pressure casting process can predict casting defects, with the needs of the market, low pressure sand casting box love more, also more and more complex. This paper mainly focuses on the design, numerical simulation and process optimization of the large complex aluminum alloy box. After numerical simulation, the optimal process is confirmed for production.According to the characteristics of the aluminum alloy box of large size, complex struct-ure, wall thickness difference, completed the design of low pressure sand casting system, process parameters and other initial process plan. The numerical simulation of the casting process is carried out, and the location and type of the defects of the casting are predicted. According to the simulation results, the process were optimized design, and get the ideal process plan through the analysis and comparison:(1) Improvement of the gating system to ensure order smooth filling.(2) The craft parameters of low pressure die casting process were simulation analysis, to determine the optimum pressure parameter 0.108 MPa, pressure time 1500 s.(3) For local thick parts increased cold iron, pouring temperature dropped to 680℃.(4) Ensure the casting according to the expected solidification sequence of solidification. The strengthening of refining gas in the smelting process, control of liquid alloy containing gas produced to help reduce defects. Finally, the high quality castings are obtained by the optimized process scheme.